CS0-003 CompTIA CyberSecurity Analyst CySA+ Certification Exam Question and Answers

Step 1: Reviewing the Vulnerability Remediation Timeframes

The remediation standards require servers to be patched based on their CVSS score:

CVSS > 9.0: Patch within 7 days

CVSS 7.9 - 9.0: Patch within 14 days

CVSS 5.0 - 7.9: Patch within 30 days

CVSS 0 - 5.0: Patch within 60 days

Step 2: Analyzing the Output Tab

From the Output tab:

Server 192.168.76.5 has a CVSS score of 9.2 for an unsupported Microsoft IIS version, indicating a critical vulnerability requiring a patch within 7 days.

Server 192.168.76.6 has a CVSS score of 7.4 for a missing secure attribute on HTTPS cookies, which falls in the 5.0 - 7.9 range, requiring a patch within 30 days.

Since the question asks for the server to be patched within 14 days, we need to focus on servers with CVSS 7.9 - 9.0:

None of the servers have a CVSS score that falls precisely in the 7.9 - 9.0 range.

However, 192.168.76.5, with a CVSS score of 9.2, has a vulnerability that necessitates a quick response and fits as it must be patched within the shortest timeframe (7 days, which includes 14 days).

The server that fits within a 14-day urgency, based on standard practices, would be 192.168.76.5.

Step 3: Reviewing the Environment Tab

The Environment Tab provides additional context for 192.168.76.5:

It’s in the dev environment, which is internal and not publicly accessible.

MFA is required, indicating security measures are already present.

Step 4: Selecting the Appropriate Technique and Mitigation

For 192.168.76.5, with the Microsoft IIS unsupported version:

Patch; upgrade IIS to the current release is the most suitable option, as upgrading IIS will resolve the unsupported software vulnerability by bringing it up-to-date with supported versions.

This technique addresses the root cause, which is the unpatched, outdated software.

Summary

Server to be patched within 14 calendar days: 192.168.76.5

Appropriate technique and mitigation: Patch; upgrade IIS to the current release

This approach ensures that the most critical vulnerabilities are addressed promptly, maintaining security compliance.

Reverse engineering is a technique that involves analyzing a binary file to understand its structure, functionality, and behavior. Reverse engineering can help security analysts perform malware analysis, vulnerability research, exploit development, and software debugging. Reverse engineering can be done using various tools, such as disassemblers, debuggers, decompilers, and hex editors.

SVR02 has a CVSS score of 7.1 and is exploitable, making itthe highest priority for remediation​.

SVR01 (CVSS 8.9) is not exploitable, so it is a lower risk.

SVR03 (CVSS 3.5) is exploitablebut has alower severitythan SVR02.

SVR04 (CVSS 6.7) is not exploitable, reducing its urgency.

Thus,B (SVR02) is the correct answer, as it presentsthe highest immediate risk​.

Limiting user creation to administrators only would work best to mitigate the attack represented by this snippet. The snippet shows an attempt to exploit a zero-day vulnerability in the ThemeREX Addons WordPress plugin, which allows remote code execution by invoking arbitrary PHP functions via the REST-API endpoint /wp-json/trx_addons/V2/get/sc_layout. In this case, the attacker tries to use the wp_insert_user function to create a new administrator account on the WordPress site12. Limiting user creation to administrators only would prevent the attacker from succeeding, as they would need to provide valid administrator credentials to create a new user. This can be done by using a plugin or a code snippet that restricts user registration to administrators34. Limiting layout creation to administrators only, setting the directory trx_addons to read only for all users, and setting the directory v2 to read only for all users are not effective controls to mitigate the attack, as they do not address the core of the vulnerability, which is the lack of input validation and sanitization on the REST-API endpoint. Moreover, setting directories to read only may affect the functionality of the plugin or the WordPress site56. References: Zero-Day Vulnerability in ThemeREX Addons Now Patched - Wordfence, Mitigating Zero Day Attacks With a Detection, Prevention … - Spiceworks, How to Restrict WordPress User Registration to Specific Email …, How to Limit WordPress User Registration to Specific Domains, WordPress File Permissions: A Guide to Securing Your Website, WordPress File Permissions: What is the Ideal Setting?

The MITRE ATT&CK framework is specifically designed for tracking Tactics, Techniques, and Procedures (TTPs) associated with cyber threats. It provides a detailed matrix of known adversarial behaviors, which is useful for correlating SIEM data to known attack patterns. According to CompTIA CySA+, MITRE ATT&CK is an industry-standard framework for threat intelligence and behavior analysis, making it the ideal tool for tracking malicious IP addresses and understanding their tactics. Other options like OSSTMM, the Diamond Model, and OWASP do not focus on TTPs as directly as MITRE ATT&CK does.

The correct answer is B. Replace the current MD5 with SHA-256.

The vulnerability that the security analyst is able to exploit is a hash collision, which is a situation where two different files produce the same hash value. Hash collisions can allow an attacker to bypass the integrity or authentication checks that rely on hash values, and submit malicious files to the system. The web application uses MD5, which is a hashing algorithm that is known to be vulnerable to hash collisions. Therefore, the analyst should suggest replacing the current MD5 with SHA-256, which is a more secure and collision-resistant hashing algorithm.

The other options are not the best suggestions to mitigate the vulnerability with the fewest changes to the current script and infrastructure. Deploying a WAF (web application firewall) to the front of the application (A) may help protect the web application from some common attacks, but it may not prevent hash collisions or detect malicious files. Deploying an antivirus application on the hosting system © may help scan and remove malicious files from the system, but it may not prevent hash collisions or block malicious files from being submitted. Replacing the MD5 with digital signatures (D)may help verify the authenticity and integrity of the files, but it may require significant changes to the current script and infrastructure, as digital signatures involve public-key cryptography and certificate authorities.

According to the CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition1, the best technique to provide the necessary assurance for embedded software that drives centrifugal pumps at a power plant is formal methods. Formal methods are a rigorous and mathematical approach to software development and verification, which can ensure the correctness and reliability of critical software systems. Formal methods can be used to specify, design, implement, and verify embedded software using formal languages, logics, and tools1.

Containerization, manual code reviews, and static and dynamic analysis are also useful techniques for software assurance, but they are not as rigorous or comprehensive as formal methods. Containerizationis a method of isolating and packaging software applications with their dependencies, which can improve security, portability, and scalability. Manual code reviews are a process of examining the source code of a software program by human reviewers, which can help identify errors, vulnerabilities, and compliance issues. Static and dynamic analysis are techniques of testing and evaluating software without executing it (static) or while executing it (dynamic), which can help detect bugs, defects, and performance issues1.

The string provided ispercent-encoded text, commonly used toobfuscate URLs. When decoded, it translates towww.ice-ptic.com. Such encoding is used tobypass email security filtersandspam detectors, making the malicious link appear as benign or unreadable to the automated scanners.

Option Ais incorrect: The string does not match JavaScript shellcode formats.

Option CandDare unlikely and unrelated to the actual behavior.

?Reference:

CySA+ All-in-One Exam Guide by Mya Heath– Chapter 4, Obfuscated Links

CompTIA Exam Objectives: 1.2 – Indicators of Malicious Activity

The signature of the malware is a unique identifier that can be used to compare it with known malware samples and their behaviors. Open-source threat intelligence sources provide information on various types of malware, their indicators of compromise, and their mitigation strategies. By cross-referencing the signature with these sources, the analyst can determine the type of malware and its telemetry. The other options are not relevant for this purpose: configuring the EDR to perform a full scan may not provide additional information on the malware type; transferring the malware to a sandbox environment may expose the analyst to further risks; logging in to the affected systems and running netstat may not reveal the malware activity.

When prioritizing vulnerabilities, analysts consider theCVSS score, whether the system isinternet-facing, and ifsensitive datais involved. The primary goal is to mitigate the mostexploitableandimpactfulrisks first.

Let's break down the key components:

Attack Vector (AV): Whether the attack can be launched remotely (N = Network) or locally (L = Local).

Attack Complexity (AC): The difficulty of executing the attack (L = Low, H = High).

Privileges Required (PR): The level of access needed for exploitation (N = None, L = Low, H = High).

User Interaction (UI): Whether user interaction is required for the attack (N = No, R = Required).

Scope (S): Whether the attack affects other systems (C = Changed, U = Unchanged).

Confidentiality (C), Integrity (I), Availability (A): The impact level (H = High, L = Low, N = None).

Evaluating Each System:

System 1 (CVSS: AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:H)

Internet-facing✅

No sensitive data❌

High confidentiality and availability impact✅

Moderate risk due to requiring low privileges

System 2 (CVSS: AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:H)

Not internet-facing❌

No sensitive data❌

Lower priority since it’s local-only

System 3 (CVSS: AV:P/AC:H/PR:H/UI:R/S:U/C:N/I:N/A:L)

Internet-facing✅

Contains sensitive data✅

But very low likelihood of exploit (requires physical access, high privileges, user interaction)

Lower priority due to high attack complexity

System 4 (CVSS: AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:H)

Internet-facing✅

No sensitive data❌

No privileges required for exploitation✅

High impact on confidentiality and availability✅

Most critical due to remote exploitability and system-wide scope

System 5 (CVSS: AV:L/AC:H/PR:H/UI:R/S:U/C:L/I:N/A:N)

Internet-facing✅

Contains sensitive data✅

But requires high privileges, high attack complexity, and user interaction

Lower priority than System 4

System 6 (CVSS: AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:H)

Not internet-facing❌

No sensitive data❌

Same as System 2 (low priority due to being local-only)

Final Decision: Patch System 4 First

System 4 is themost criticalbecause:

It isinternet-facing(higher exposure).

It has ahigh CVSS score.

Itrequires no privileges(easy to exploit).

It hassystem-wide scope impact(can affect other systems).

Thus, it should bepatched firstto minimize security risks.

The incident response policy or plan is a document that defines the roles and responsibilities, procedures and processes, communication and escalation protocols, and reporting and documentation requirements for handling security incidents. The lead should review what is documented in the incident response policy or plan to determine who should be communicated with and when during a security incident, as well as what information should be shared and how. The incident response policy or plan should also be aligned with the organizational policies and legal obligations regarding incident notification and disclosure.

A vulnerability scan is a process of identifying and assessing the security weaknesses of a system or network. A vulnerability scan can help a security analyst to effectively identify the most security risks associated with a locally hosted server, such as missing patches, misconfigurations, outdated software, or exposed services. A vulnerability scan can also provide recommendations on how to remediate the identified vulnerabilities and improve the security posture of the server12 References: 1: What is a Vulnerability Scan? | Definition and Examples 2: Securing a server: risks, challenges and best practices - Vaadata

Searching for other mail users who have received the same file is the best activity to perform next, as it helps to identify and contain the scope of the ransomware attack and prevent further damage. Ransomware is a type of malware that encrypts files on a system and demands payment for their decryption. Ransomware can spread through phishing emails that contain malicious attachments or links that download the ransomware. By searching for other mail users who have received the same file, the analyst can alert them not to open it, delete it from their inboxes, and scan their systems for any signs of infection. The other activities are not as urgent or effective as searching for other mail users who have received the same file, as they do not address the immediate threat of ransomware spreading or affecting more systems. Wiping the computer and reinstalling software may restore the functionality of the affected workstation, but it will also erase any evidence of the ransomware attack and make recovery of encrypted files impossible. Shutting down the email server and quarantining it from the network may stop the delivery of more phishing emails, but it will also disrupt normal communication and operations for the organization. Acquiring a bit-level image of the affected workstation may preserve the evidence of the ransomware attack, but it will not help to stop or remove the ransomware or decrypt the files.

The best practice for securing access to sensitive data is to implement multifactor authentication (MFA), which combines multiple factors of authentication to enhance security.

Option B (Biometrics + Device with a Personalized Code) uses two strong factors:

Biometrics (something you are)

A device with a personalized code (something you have)This combination significantly reduces the risk of unauthorized access​.

Option A (Randomized Code) is good but weaker than biometrics because it relies only on something you have.

Option C (Passphrase) is single-factor authentication, which is susceptible to brute-force attacks​.

Option D (One-time Code + Push Notification) is useful, but email-based authentication can be vulnerable to phishing and MITM attacks.

Comprehensive and Detailed Step-by-Step Explanation:Non-persistent virtual desktop infrastructures (VDIs) are the most suitable choice to ensure consistent security across different locations. Non-persistent VDIs revert to their original state after a session, reducing the risk of data leakage or malware persistence. These systems are centrally managed, ensuring uniform security policies regardless of the user's location.

To determine the highest priority for remediation, we must compare the configuration of each VM against the three mandatory security requirements:

No public IPs

All data secured at rest (Encryption = Yes)

No insecure ports/protocols (No unencrypted protocols like HTTP/Telnet)

1. Analyze the Compliance of VM_PRD_DB (Option A):

Asset Type: Production Database (High Value Target).

IP Config: public -> FAIL. (A production database should never be directly exposed to the internet; it should reside in a private subnet).

Encryption: no -> FAIL. (Violates the "data secured at rest" policy).

Ingress Port: 80 (HTTP) -> FAIL. (Port 80 is cleartext/unencrypted. Using an insecure protocol on a public interface puts data confidentiality at immediate risk).

Conclusion: This asset violates all three security policies and exposes the organization's most critical data (Production DB) to the public internet via an insecure channel.

2. Why the other options are lower priority:

B. VM_DEV_DB:

It uses a private IP (Pass) and Port 443 (Secure). It only fails the "Encryption" check. Since it is a Development box and not publicly exposed, the risk is significantly lower.

C. VM_DEV_Web02:

It exposes Port 22 (SSH). While exposing SSH to the internet is poor practice, SSH is a secure protocol (encrypted), unlike Port 80. It also has encryption at rest enabled.

D. VM_PRD_Web01:

It exposes Port 3389 (RDP). While RDP is a common attack vector (ransomware entry point), the server has "Encryption at rest" enabled (Pass).

Comparison: While VM_PRD_Web01 is risky due to RDP, VM_PRD_DB is riskier because it involves a Database (higher impact than a web server) communicating over Port 80 (cleartext) with No Encryption at rest.

A risk register typically contains details like ID, name, description, classification of information, and responsible party. It’s used for tracking identified risks and managing them.Recording details like ID, Name, Description, Classification of information, and Responsible party is typically done in a Risk Register. This document is used to identify, assess, manage, and monitor risks within an organization. It's not directly related to incident response or change control documentation.

Making a forensic image of the device and creating a SRA-I hash is the best step to preserve evidence, as it creates an exact copy of the device’s data and verifies its integrity. A forensic image is a bit-by-bit copy of the device’s storage media, which preserves all the information on the device, including deleted or hidden files. A SRA-I hash is a cryptographic value that is calculated from the forensic image, which can be used to prove that the image has not been altered or tampered with. The other options are not as effective as making a forensic image and creating a SRA-I hash, as they may not capture all the relevant data, or they may not provide sufficient verification of the evidence’s authenticity. Official References:

https://www.sans.org/blog/forensics-101-acquiring-an-image-with-ftk-imager/

https://swailescomputerforensics.com/digital-forensics-imaging-hash-value/

Aplaybookprovides astep-by-stepguide for handling specific types of incidents like ransomware, making it invaluable during triage. It outlines predefined procedures, aiding consistent and fast decision-making.

The incident response plan (A) provides high-level structure.

Lessons learned (B) applyafterthe incident.

Tabletop exercises (D) are training tools, not live guides.

📘Reference: Chapple & Seidl, CySA+ Practice Tests, Incident Response, Chapter 3 – Playbooks and Procedures​.

📘Objective: 3.1 - Apply incident response procedures based on an incident classification​.

1. Analyze the Log Evidence: The log displays a specific sequence of rapid-fire events (within 18 seconds) characteristic of automated reconnaissance tools used to map Active Directory environments.

20:06:05 (LDAP Reads): The attacker queries the directory for high-value groups (Domain Admins) and critical infrastructure (Domain Servers). They are not trying to log in; they are reading the membership lists to see who is important and where the servers are.

20:06:09 (EDR Enumeration): The attacker checks the local Administrators group. This is to see if the current compromised user has admin rights or who does.

20:06:23 (SMB Connections): The host PC021 attempts to connect to multiple other hosts. This indicates the attacker is testing where they can move laterally using the credentials or access they currently have.

2. Why this is "Finding the Shortest Path" (Option A): This behavior is the textbook signature of tools like BloodHound (or its data collector, SharpHound).

Concept: Adversaries use these tools to visualize relationships in Active Directory. They query LDAP to find out: "I am User A. Which computers can I access? Who is a Domain Admin? Is a Domain Admin logged into a computer I can access?"

Goal: The tool calculates the mathematical "shortest path" (graph theory) from the attacker's current low-level foothold to the ultimate target (Domain Admin).

The combination of LDAP querying (mapping the graph) and SMB connection attempts (verifying sessions/local admin rights) confirms the adversary is mapping out the network to find the most efficient route to total compromise.

Why the other options are incorrect:

B. An adversary is performing a vulnerability scan: Vulnerability scanners (like Nessus or Qualys) typically probe ports and services to identify unpatched software (CVEs). They generally do not focus on querying LDAP for "Domain Admins" group membership as their primary action.

C. An adversary is escalating privileges: While the attacker intends to escalate privileges eventually, the logs show enumeration (Discovery phase). They are currently looking for the path to escalate, not actively exploiting a vulnerability (like a kernel exploit) to change their privilege level in this specific snapshot.

D. An adversary is performing a password stuffing attack: Password stuffing involves high volumes of failed authentication attempts against a login service. The logs here show read operations and connection attempts, not the "Invalid Credential" errors associated with stuffing.

The observed activity from a privileged account indicates an insider attack, which is when a trusted user or employee misuses their access rights to compromise the security of the organization. Accessing emails and sensitive information, modifying audit logs, and logging in at abnormal times are all signs of malicious behavior by a privileged user who may be trying to steal, tamper, or destroy data, or cover their tracks. An insider attack can cause significant damage to the organization’s reputation, operations, and compliance12. References: The Privileged Identity Playbook Guides Management of Privileged User Accounts, How to Track Privileged Users’ Activities in Active Directory

Intrusion Detection Systems (IDS) logs provide visibility into network traffic patterns and can help detect insecure or unusual connections. These logs will show if non-secure protocols are used, potentially revealing exposed credentials. According to CompTIA CySA+, IDS logs are essential for identifying malicious activity related to communications and network intrusions. Options like DNS (A) and tcpdump (B) provide network details, but IDS specifically monitors for intrusions and unusual activities relevant to security incidents.

To determine the correct priority, you must filter the options by applying the rules from Security Policy 1006 in the order of importance dictated by the scenario.

“The Company shall prioritize patching of publicly available systems and services over patching of internally available system.”

Option A: Internal System

Option B: External System (Keep)

Option C: External System (Keep)

Option D: Internal System

Result: Eliminate Options A and D. We are now choosing between B and C.

“In situations where a choice must be made between confidentiality and availability, the Company shall prioritize confidentiality of data over availability of systems and data.”

To apply this, you must read the CVSS v3.1 Vector String for the remaining options. The relevant metrics are C (Confidentiality) and A (Availability).

Option B (CAP.SHIELD): C:H / I:N / A:N

Confidentiality: High (C:H)

Availability: None (A:N)

Interpretation: This vulnerability allows for a significant breach of data confidentiality.

Option C (LOKI.DAGGER): C:N / I:N / A:H

Confidentiality: None (C:N)

Availability: High (A:H)

Interpretation: This vulnerability allows for a significant disruption of service (DoS).

Conclusion: Since the policy explicitly prioritizes Confidentiality (Option B) over Availability (Option C), Option B is the highest priority.

The exam expects you to parse raw CVSS strings to assess risk. Here is the breakdown for the correct answer (Option B):

Metric

Code

Value

Meaning

AV

AV:N

Network

The vulnerability is exploitable remotely via the network (most dangerous).

AC

AC:L

Low

No complex conditions are required to exploit.

PR

PR:N

None

No privileges are required (unauthenticated).

UI

UI:N

None

No user interaction is required.

C

C:H

High

Confidentiality Impact. Total loss of confidentiality.

A

A:N

None

Availability Impact. No impact to uptime.

Testing is a crucial step in any change management process, as it ensures that the change is compatible with the existing systems and does not cause any errors or disruptions. In this case, the change management team failed to test the email client patch on Windows 11 devices, which resulted in a widespread issue for the users. Testing would have revealed the problem before the patch was deployed, and allowed the team to fix it or postpone the change.

Port 3389 is commonly used by Remote Desktop Protocol (RDP), which is a service that allows remote access to a system. A vulnerability on this port could allow an attacker to compromise the web server or use it as a pivot point to access other systems. However, if the firewall blocks this port, the risk of exploitation is reduced.

The Diamond Model of Intrusion Analysis is a framework that describes the relationship between four components of a cyberattack: adversary, capability, infrastructure, and victim. It helps analysts understand the behavior and motivation of threat actors, as well as the tools and methods they use to compromise their targets12. References: Main Analytical Frameworks for Cyber Threat Intelligence, section 4; Strategies, tools, and frameworks for building an effective threat intelligence team, section 3.

In this scenario, adding the IP address to the EDR (Endpoint Detection and Response) deny list is an immediate and effective way to block further reconnaissance activities from the malicious source. EDR solutions are designed to provide advanced endpoint security, including blocking specific IP addresses and preventing potentially harmful traffic. This proactive step aligns with CompTIA Cybersecurity Analyst (CySA+) best practices for threat prevention and response. While other options, such as using SIEM for monitoring (option B) or WAF policies (option C), provide additional layers of security, they do not directly block the threat in the same immediate way that adding the IP to the EDR deny list does.

A compensating control is an alternative measure that provides a similar level of protection as the original control, but is used when the original control is not feasible or cost-effective. In this case, the CISO should develop a compensating control to mitigate the risk of the vulnerability in the ACE software, such as implementing additional monitoring, firewall rules, or encryption, until the issue can be fixed permanently by the developers. References: CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 5, page 197; CompTIA CySA+ CS0-003 Certification Study Guide, Chapter 5, page 205.

Brady should be prioritized for remediation, as it has the highest risk score and the highest number of affected users. The risk score is calculated by multiplying the CVSS score by the exposure factor, which is the percentage of systems that are vulnerable to the exploit. Brady has a risk score of 9 x 0.8 = 7.2, which is higher than any other system. Brady also has 500 affected users, which is more than any other system. Therefore, patching brady would reduce the most risk and impact for the organization. The other systems have lower risk scores and lower numbers of affected users, so they can be remediated later.

The correct answer is A. To ensure the report is legally acceptable in case it needs to be presented in court.

Proper handling and reporting of existing evidence are important for the investigation and reporting phases of an incident response because they ensure the integrity, authenticity, and admissibility of the evidence in case it needs to be presented in court. Evidence that is mishandled, tampered with, or poorly documented may not be accepted by the court or may be challenged by the opposing party. Therefore, incident responders should follow the best practices and standards for evidence collection, preservation, analysis, and reporting1.

The other options are not reasons why proper handling and reporting of existing evidence are important for the investigation and reporting phases of an incident response. They are rather outcomes or benefits of conducting a thorough and effective incident response process. A lessons-learned analysis (B) is a way to identify the strengths and weaknesses of the incident response team and improve their performance for future incidents. A postmortem analysis © is a way to determine the root cause, impact, and timeline of the incident and provide recommendations for remediation and prevention. A root cause analysis (D) is a way to identify the underlying factors that led to the incident and address them accordingly.

tcpdump is a command-line tool that can capture and analyze network packets from a given interface or file. The -n option prevents tcpdump from resolving hostnames, which can speed up the analysis. The -r option reads packets from a file, in this case packets.pcap. The host [IP address] filter specifies that tcpdump should only display packets that have the given IP address as either the source or thedestination. This command can help the security analyst detect connections to a suspicious IP address by collecting the packet captures from the gateway. Official References:

https://partners.comptia.org/docs/default-source/resources/comptia-cysa-cs0-002-exam-objectives

https://www.techtarget.com/searchsecurity/quiz/Sample-CompTIA-CySA-test-questions-with-answers

https://www.reddit.com/r/CompTIA/comments/tmxx84/passed_cysa_heres_my_experience_and_how_i_studied/

After recovering a compromised server to its previous state, the analyst should perform forensic analysis to determine the root cause, impact, and scope of the incident, as well as to identify any indicators of compromise, evidence, or artifacts that can be used for further investigation or prosecution. References: CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 6, page 244; CompTIA CySA+ CS0-003 Certification Study Guide, Chapter 6, page 253.

A security analyst’s concern is that any discovered vulnerabilities in the OS that is approaching the end-of-life date will not be remediated by the vendor, leaving the system exposed to potential attacks. The other options are not directly related to the security analyst’s role or responsibility. Verified References: CompTIA Cybersecurity Analyst (CySA+) Certification Exam Objectives, page 9, section 2.21

The vulnerability that should be patched first, given the above third-party scoring system, is:

TSpirit: Cobain: Yes Grohl: Yes Novo: Yes Smear: No Channing: No

This vulnerability has three out of five metrics marked as Yes, which indicates a high severity level. The metrics Cobain, Grohl, and Novo are more important than Smear and Channing, according to the vulnerability management team. Therefore, this vulnerability poses a greater risk than the other vulnerabilities and should be patched first.

The log output indicates an attempt to execute a command via an unsecured service account, specifically using a wget command to download a file from an external source. This suggests that the adversary is trying to exploit a vulnerability in the web server to run unauthorized commands, which is a common technique for gaining a foothold or further compromising the system. The presence of wget http://grohl.ve.da/tmp/brkgtr.zip indicates an attempt to download and possibly execute a malicious payload.

This is a type of web application vulnerability called cross-site scripting (XSS), which allows an attacker to inject malicious code into a web page that is viewed by other users. XSS can be used to steal cookies, session tokens, credentials, or other sensitive information, or to perform actions on behalf of the victim.

Input sanitization is a technique that prevents XSS attacks by checking and filtering the user input before processing it. Input sanitization can remove or encode any characters or strings that may be interpreted as code by the browser, such as <, >, ", ', or javascript:. Input sanitization can also validate the input against a predefined format or range of values, and reject any input that does not match.

Output encoding is a technique that prevents XSS attacks by encoding the output before sending it to the browser. Output encoding can convert any characters or strings that may be interpreted as code by the browser into harmless entities, such as <, >, ", ', or javascript:. Output encoding can also escape any special characters that may have a different meaning in different contexts, such as , /, or ;.

Code obfuscation is a technique that makes the source code of a web application more difficult to read and understand by humans. Code obfuscation can use techniques such as renaming variables and functions, removing comments and whitespace, replacing literals with expressions, or adding dummy code. Code obfuscation can help protect the intellectual property and trade secrets of a web application, but it does not prevent XSS attacks.

The correct answer is A. Address space layout randomization.

Address space layout randomization (ASLR) is a security control that randomizes the memory address space of a process, making it harder for an attacker to exploit memory-based vulnerabilities, such as buffer overflows1. ASLR can also prevent a security analyst from finding the proper memory address of a piece of malicious code, as the memory address changes every time the process runs2.

The other options are not the best explanations for why the memory address changes every time the process runs. Data execution prevention (B) is a security control that prevents code from being executed in certain memory regions, such as the stack or the heap3. Stack canary © is a security technique that places a random value on the stack before a function’s return address, to detect and prevent stack buffer overflows. Code obfuscation (D) is a technique that modifies the source code or binary of a program to make it more difficult to understand or reverse engineer. These techniques do not affect the memory address space of a process, but rather the execution or analysis of the code.

The output shows that the web application has a cross-origin resource sharing (CORS) header that allows any origin to access its resources. This is a security misconfiguration that could allow malicious websites to make requests to the web application on behalf of the user and access sensitive data or perform unauthorized actions. The tuning recommendation is to configure the Access-Control-Allow-Origin header to only allow authorized domains that need to access the web application’s resources. This would prevent unauthorized cross-origin requests and reduce the risk of cross-site request forgery (CSRF) attacks.

The snippet shows an attempt to access the boot.ini file, which is a configuration file for Windows operating systems. The “… \ … /” pattern is used to navigate up the directory structure and reach the root directory, where the boot.ini file is located. This is a common technique for exploiting directory traversal vulnerabilities, which allow an attacker to access files and directories outside the intended web server path. The other options are not relevant for this purpose: remote file inclusion involves injecting a malicious file into a web application; cross-site scripting involves injecting malicious scripts into a web page; remote code execution involves executing arbitrary commands on a remote system; enumeration of /etc/passwd involves accessing the file that stores user information on Linux systems.

SQL injection should be remediated first, as it is a high-severity vulnerability that can allow an attacker to execute arbitrary SQL commands on the database server and access, modify, or delete sensitive data, including PII. According to the Arachni scan results, there are two instances of SQL injection and three instances of blind SQL injection (two timing attacks and one differential analysis) in the web application. These vulnerabilities indicate that the web application does not properly validate or sanitize the user input before passing it to the database server, and thus exposes the database to malicious queries12. SQL injection can have serious consequences for the confidentiality, integrity, and availability of the data and the system, and can also lead to further attacks, such as privilege escalation, data exfiltration, or remote code execution34. Therefore, SQL injection should be the highest priority for remediation, and the web application should implement input validation, parameterized queries, and least privilege principle to prevent SQL injection attacks5. References: Web application testing with Arachni | Infosec, How do I create a generated scan report for PDF in Arachni Web …, Command line user interface · Arachni/arachni Wiki · GitHub, SQL Injection - OWASP, Blind SQL Injection - OWASP, SQL Injection Attack: What is it, and how to prevent it., SQL Injection Cheat Sheet & Tutorial | Veracode

The correct answer is B. Allowlisting.

Allowlisting is a technique that allows only pre-approved web-based software to run on a system or network, while blocking all other software. Allowlisting can help prevent unauthorized or malicious software from compromising the security of an organization. Allowlisting can be implemented using various methods, such as application control, browser extensions, firewall rules, or proxy servers12.

The other options are not the best techniques to ensure that users only leverage web-based software that has been pre-approved by the organization. Blocklisting (A) is a technique that blocks specific web-based software from running on a system or network, while allowing all other software. Blocklisting can be ineffective or inefficient, as it requires constant updates and may not catch all malicious software. Graylisting © is a technique that temporarily rejects or delays incoming messages from unknown or suspicious sources, until they are verified as legitimate. Graylisting is mainly used for email filtering, not for web-based software control. Webhooks (D) are a technique that allows web-based software to send or receive data from other web-based software in real time, based on certain events or triggers. Webhooks are not related to web-based software control, but rather to web-based software integration.

The shell script function that could help identify possible network addresses from different source networks belonging to the same company and region is:

function y() { dig $(dig -x $1 | grep PTR | tail -n 1 | awk -F ”.in-addr” ’{print $1}’).origin.asn.cymru.com TXT +short }

This function takes an IP address as an argument and performs two DNS lookups using the dig command. The first lookup uses the -x option to perform a reverse DNS lookup and get the hostname associated with the IP address. The second lookup uses the origin.asn.cymru.com domain to get the autonomous system number (ASN) and other information related to the IP address, such as the country code, registry, or allocation date. The function then prints the IP address and the ASN information, which can help identify any network addresses that belong to the same ASN or region

User behavior analysis (UBA) is the most effective method for detecting abnormal account activity.

UBA uses machine learning and behavioral analytics to identify patterns in how users interact with systems. If an employee suddenly logs in from an unusual location or accesses resources outside of their normal behavior, it raises an alert​.

Option A (Malicious command interpretation) is focused on malware analysis, not user behavior.

Option B (Network monitoring) detects anomalies at the network level, but does not specifically focus on user behaviors.

Option D (SSL Inspection) is useful for decrypting encrypted traffic, but it does not analyze user activity patterns.

Using aregular expression (regex)to search email logs is the most efficient and scalable way to identify patterns in phishing URLs. Phishing campaigns often use consistent URL formats across different domains. Regex allows administrators to define flexible patterns to match these URLs even when the domains vary. This is significantly more effective than relying on user reports or less granular tools like firewall logs for such cases.

Part 1:

Part 2:

Based on the compliance report, I recommend the following changes for each server:

AppServ1: No changes are needed for this server.

AppServ2: Disable or upgrade TLS 1.0 and TLS 1.1 to TLS 1.2 on this server to ensure secure encryption and communication between clients and the server. Update Apache from version 2.4.17 to version 2.4.18 or greater on this server to fix any potential vulnerabilities or bugs.

AppServ3: Downgrade Apache from version 2.4.19 to version 2.4.18 or lower on this server to ensure compatibility and stability with the company’s applications and policies. Change the port number from 8080 to either port 80 (for HTTP) or port 443 (for HTTPS) on this server to follow the default port convention and avoid any confusion or conflicts with other services.

AppServ4: Update Apache from version 2.4.16 to version 2.4.18 or greater on this server to fix any potential vulnerabilities or bugs. Change the port number from 8443 to either port 80 (for HTTP) or port 443 (for HTTPS) on this server to follow the default port convention and avoid any confusion or conflicts with other services.

The most likely cause of the issue where an ICS (Industrial Control System) could not be updated due to hardware versioning incompatibility is a legacy system. Legacy systems often have outdated hardware and software that may not be compatible with modern updates and patches. This can pose significant challenges in maintaining security and operational efficiency.

The vulnerability scan shows that the version information is visible in the http-server-header, which can be exploited by attackers to identify vulnerabilities specific to that version. Removing or obfuscating this information can enhance security.

Deploying an additional layer of access controls to verify authorized individuals is the best compensating control for the authentication vulnerability that could bypass the primary control. A compensating control is a security measure that is implemented to mitigate the risk of a vulnerability ora threat when the primary control is not sufficient or feasible. A compensating control should provide a similar or greater level of protection as the primary control, and should be closely related to the vulnerability or the threat it is addressing1. In this case, the primary control is to restrict access to a sensitive database, and the vulnerability is an authentication bypass. Therefore, the best compensating control is to deploy an additional layer of access controls, such as multifactor authentication, role-based access control, or encryption, to verify the identity and the authorization of the individuals who are accessing the database. This way, the compensating control can prevent unauthorized access to the database, even if the primary control is bypassed23. Running regular penetration tests, conducting regular security awareness training, and implementing intrusion detection software are all good security practices, but they are not compensating controls for the authentication vulnerability, as they do not provide a similar or greater level of protection as the primary control, and they are not closely related to the vulnerability or the threat they are addressing. References: Compensating Controls: An Impermanent Solution to an IT … - Tripwire, What is Multifactor Authentication (MFA)? | Duo Security, Role-Based Access Control (RBAC) and Role-Based Security, [What is a Penetration Test and How Does It Work?]

In case of a phishing attack, it’s crucial to review what actions were taken by the employee and analyze the phishing email to understand its nature and impact.References: CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 6, page 246; CompTIA CySA+ CS0-003 Certification Study Guide, Chapter 6, page 255.

The best way to see the entire contents of the downloaded files in Wireshark is to change the display filter to ftp-data and follow the TCP streams. FTP-data is a protocol that is used to transfer files between an FTP client and server using TCP port 20. By filtering for ftp-data packets and following the TCP streams, the analyst can see the actual file data that was transferred during the FTP session

Multifactor authentication (MFA) is a security method that requires users to provide two or more pieces of evidence to verify their identity, such as a password, a PIN, a fingerprint, or a one-time code. MFA can reduce the impact of a credential leak because even if the attackers have the usernames and passwords of the employees, they would still need another factor to access the organization’s systems and resources. Password changes, system hardening, and password encryption are also good security practices, but they do not address the immediate threat of compromised credentials.

Passive scanning is a method of vulnerability identification that does not send any packets or probes to the target devices, but rather observes and analyzes the network traffic passively. Passive scanning can minimize the risk of OT/ICS devices malfunctioning due to the vulnerability identification process, as it does not interfere with the normal operation of the devices or cause any network disruption. Passive scanning can also detect vulnerabilities that active scanning may miss, such as misconfigured devices, rogue devices or unauthorized traffic. Official References:

https://partners.comptia.org/docs/default-source/resources/comptia-cysa-cs0-002-exam-objectives

https://www.comptia.org/blog/the-new-comptia-cybersecurity-analyst-your-questions-answered

https://www.comptia.org/certifications/cybersecurity-analyst

Mean Time to Detect (MTTD) is the most appropriate Key Performance Indicator (KPI) to monitor the effectiveness of an incident response reporting and communication program among the choices provided.

Why B is correct: The primary goal of an "incident reporting" program (whether automated by tools or reported by users/staff) is to alert the security team to an issue as quickly as possible. MTTD measures the average time it takes for an organization to identify (detect and report) an incident after it has occurred. A lower MTTD directly indicates that the reporting mechanisms and communication channels from the source to the analysts are operating effectively.

Why A is incorrect: Incident volume measures the quantity of incidents, which reflects the threat landscape or workload rather than the effectiveness of the response program itself. While an increase in user-reported volume can indicate better awareness, MTTD is the standard performance metric for the process.

Why C is incorrect: Average time to patch is a KPI for Vulnerability Management, not Incident Response reporting.

Why D is incorrect: Remediated incidents refers to the volume of resolved issues (Response/Recovery phase) and does not specifically measure the speed or quality of the reporting and communication (detection) phase.

In Domain 4 (Reporting and Communication) and Domain 1 (Security Operations), CompTIA emphasizes the use of time-based metrics to evaluate process maturity.

MTTD (Mean Time to Detect): Measures "dwell time" and the efficiency of the Detection & Reporting phase.

MTTR (Mean Time to Respond): Measures the efficiency of the Response & Recovery phase.

​

A lessons-learned review is a process of evaluating the effectiveness and efficiency of the incident response plan after an incident or an exercise. The purpose of the review is to identify the strengths and weaknesses of the incident response plan, and to update it accordingly to improve the future performance and resilience of the organization. Therefore, the incident response plan should be updated after a lessons-learned review.

Automatingthe generation of NIDS (Network Intrusion Detection System) rulesbased onStructured Threat Information eXpression (STIX) messagesis apractical use of automationin security operations​.

Option B (Privileged access requests)should involve human oversight due to thehigh risk of unauthorized access.

Option C (PKI identity verification)requires manualdocument verificationandhuman approval.

Option D (Malware analysis)often requiressandboxing and behavioral analysis, which benefit from human expertise.

Thus,A is the correct answer, asautomating threat intelligence ingestion and rule creation enhances efficiency in intrusion detection​.

Mean time to detect (MTTD) is the best metric for an organization to focus on given recent investments in SIEM, SOAR, and a ticketing system. MTTD is a metric that measures how long it takes to detect a security incident or threat from the time it occurs. MTTD can be improved by using tools and processes that can collect, correlate, analyze, and alert on security data from various sources. SIEM, SOAR, and ticketing systems are examples of such tools and processes that can help reduce MTTD and enhance security operations. Official References: https://www.eccouncil.org/cybersecurity-exchange/threat-intelligence/cyber-kill-chain-seven-steps-cyberattack

Proprietary systems are systems that are owned and controlled by a specific vendor or manufacturer, and that use proprietary standards or protocols that are not compatible with other systems. Proprietary systems can pose a challenge for vulnerability management, as they may not allow users to access or modify their configuration, update their software, or patch their vulnerabilities. In this case, two of the critical systems cannot be upgraded due to a vendor appliance that the company does not have access to. This indicates that these systems and associated vulnerabilities are examples of proprietary systems as inhibitors to remediation

Deduplication is a process that involves removing any duplicate or redundant data or information from a data set or source. Deduplication can help consolidate several threat intelligence feeds by eliminating any overlapping or repeated indicators of compromise (IoCs), alerts, reports, or recommendations. Deduplication can also help reduce the volume and complexity of threat intelligence data, as well as improve its quality, accuracy, or relevance.

A web application firewall (WAF) is a tool that can protect web servers from attacks such as SQL injection, cross-site scripting, and other web-based threats. A WAF can filter, monitor, and block malicious HTTP traffic before it reaches the web server. A WAF can also be configured with rules and policies to detect and prevent specific types of attacks.

Hacktivists are threat actors who use cyberattacks to promote a social or political cause, such as environmentalism, human rights, or democracy. They may target companies that they perceive as violating their values or harming the public interest. Hacktivists often use techniques such as defacing websites, launching denial-of-service attacks, or leaking sensitive data to expose or embarrass their targets12. References: An introduction to the cyber threat environment, page 3; What is a Threat Actor? Types & Examples of Cyber Threat Actors, section 2.

The user has become an insider threat by downloading software that contains malware onto a computer that eventually infects numerous other systems. An insider threat is a person or entity that has legitimate access to an organization’s systems, networks, or resources and uses that access to cause harm or damage to the organization. An insider threat can be intentional or unintentional, malicious or negligent, and can result from various actions or behaviors, such as downloading unauthorized software, violating security policies, stealing data, sabotaging systems, or collaborating with external attackers.

A Secure Software Development Life Cycle (SDLC) integrates security measures at each stage of development to reduce vulnerabilities and improve the overall security of the software. This is essential for minimizing risks related to software usage and ensuring compliance with regulatory requirements, which is particularly important for organizations handling sensitive data. As per CompTIA standards, a Secure SDLC helps prevent security breaches and protects both the organization and its users from potential harm. Options A, C, and D do not accurately describe the primary goals of a Secure SDLC, which primarily centers on risk reduction and regulatory compliance.

Based on the list of hosts and their functions, DCEast01, which is a Domain Controller, would be the most pivotal in the distribution of an encryption binary via Group Policy. Domain Controllers are responsible for security and administrative policies within a Windows Domain. Group Policy is a feature of Windows that facilitates a wide range of advanced settings that administrators can use to control the working environment of user accounts and computer accounts. Group Policy can be used to deploy software, which in this case would be the encryption binary of the ransomware. SQL01 is a database server and unlikely to be used for this purpose. WK10-Sales07 and WK7-Plant01 are client machines, and HQAdmin9, although it is a network admin laptop, would not typically be used to distribute policies across a network.

 XSS (cross-site scripting) is the vulnerability type that the security analyst is validating, as the snippet shows an attempt to inject a script tag into the web application. XSS is a web security vulnerability that allows an attacker to execute arbitrary JavaScript code in the browser of another user who visits the vulnerable website. XSS can be used to perform various malicious actions, such as stealing cookies, session hijacking, phishing, or defacing websites. The other vulnerability types are not relevant to the snippet, as they involve different kinds of attacks. Directory traversal is an attack that allows an attacker to access files and directories that are outside of the web root folder. XXE (XML external entity) injection is an attack that allows an attacker to interfere with an application’s processing of XML data, and potentially access files or systems. SSRF (server-side request forgery) is an attack that allows an attacker to induce the server-side application to make requests to an unintended location. Official References:

https://portswigger.net/web-security/xxe

https://portswigger.net/web-security/ssrf

https://cheatsheetseries.owasp.org/cheatsheets/Server_Side_Request_Forgery_Prevention_Cheat_Sheet.html

Sandboxing is a technique that isolates potentially malicious programs or files in a controlled environment, preventing them from affecting the rest of the system. It can help mitigate the effects of a new ransomware attack by preventing it from encrypting or deleting important data or spreading to other devices. References: CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 5, page 202; CompTIA CySA+ CS0-003 Certification Study Guide, Chapter 5, page 210.

From the logs, PC3 showsoutlook.exe spawning excel.exe at 1:15 PM, and laterexcel.exe spawning procdump.exe at 1:16 PM. This is highly suspicious becauseoutlook.exe should not normally launch Excel, andprocdump.exe is often used by attackers to dump process memory, which is a common technique in credential theft​.

PC1:Running expected Windows processes (wininit.exe spawning services.exe and lsass.exe).

PC2:Running a browser process (chrome.exe) from explorer.exe, which is normal.

PC3:Highly suspicious behavior (Excel spawning procdump.exe).

PC4:Running mstsc.exe (Remote Desktop) from explorer.exe, which is expected.

PC5:Running Firefox from explorer.exe, which is normal.

Thus,PC3 should be prioritized for investigationdue to its potential involvement in credential theft.

The vulnerability with the highest CVSS score and an active exploit is Microsoft CVE-2021-34527 (PrintNightmare). Although only present on two instances, its high severity (8.4) and exploitable nature make it a priority. PrintNightmare is a well-known remote code execution vulnerability, which can be a critical risk. According to CompTIA CySA+ and vulnerability management practices, prioritizing based on severity and exploitability is essential, even over the number of instances. Other vulnerabilities listed are less severe or lack active exploitation.

Implementing input validation is the best way to mitigate the buffer overflow vulnerability at the application level. Input validation is a technique that checks the data entered by users or attackers against a set of rules or constraints, such as data type, length, format, or range. Input validation can prevent common web application attacks such as SQL injection, cross-site scripting (XSS), or command injection, which exploit the lack of input validation to execute malicious code or commands on the server or the client side. By validating the input before allowing submission, the web application can reject or sanitize any malicious or unexpected input, and protect the application from being compromised12. References: How to detect, prevent, and mitigate buffer overflow attacks - Synopsys, How to mitigate buffer overflow vulnerabilities | Infosec

The one-liner script is utilizing JavaScript to execute a PowerShell command that downloads and runs a script from an external source, indicating the use of custom malware to download an additional script. References: CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 4: Security Operations and Monitoring, page 156.

The activities taken by the process with PID 1024 will provide the best insight into this potentially malicious process, based on the anomalous behavior. BGInfo.exe is a legitimate tool that displays system information on the desktop background, but it can also be used by attackers to gather information about the compromised host or to disguise malicious processes12. By monitoring the activities of PID 1024, such as the files it accesses, the network connections it makes, or the commands it executes, the analyst can determine if the process is benign or malicious.

Threat modelingis aproactiveapproach used toidentify, analyze, and mitigate potential threatsbefore they impact production systems. It is especially useful in early development stages to anticipate vulnerabilities and attack paths​.

Option B (Penetration testing)is areactive measureperformed on deployed systems, rather than prior to production.

Option C (Bug bounty)programs incentivize external researchers but do not proactively model risksbefore deployment.

Option D (SDLC training)improves security awareness but does notactively assess risks.

Thus,A (Threat modeling) is the best choice, as it enablesearly identification and mitigation of security risks​.

The first action that the analyst should take in this case is to clone the virtual server for forensic analysis. Cloning the virtual server involves creating an exact copy or image of the server’s data and state at a specific point in time. Cloning the virtual server can help preserve and protect any evidence or information related to the security incident, as well as prevent any tampering, contamination, or destruction of evidence. Cloning the virtual server can also allow the analyst to safely analyze and investigate the incident without affecting the original server or its operations.

The suspicious entry on the host-based IDS logs indicates that a reverse shell was executed on the host, which connects to the remote IP address 10.1.2.3 on port 8080. The shell script option D uses the netstat command to check if there is any active connection to that IP address and port, and prints “Malicious activity” if there is, or “OK” otherwise. This is the most accurate way to confirm if the reverse shell is still active, as the other options may not detect the connection or may produce false positives.

ReferencesCompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 8: Incident Response, page 339.Reverse Shell Cheat Sheet, Bash section.

The MITRE ATT&CK framework is widely used for tracking and categorizing Tactics, Techniques, and Procedures (TTPs) of adversaries. TTPs help analysts understand the behaviors and methods attackers employ during incidents, making this framework particularly useful in SIEM dashboards for correlating and identifying threats. While the other options (OSSTMM, Diamond Model, OWASP) offer various security methodologies, MITRE ATT&CK is specifically focused on documenting adversary behaviors, making it the best fit here. CompTIA CySA+ often emphasizes MITRE ATT&CK for mapping and understanding threat behaviors in incident response.

Automation is the best concept to describe the example, as it reflects the use of technology to perform tasks or processes without human intervention. Automation can help to improve efficiency, accuracy, consistency, and scalability of various operations, such as identity and access management (IAM). IAM is a security framework that enables organizations to manage the identities and access rights of users and devices across different systems and applications. IAM can help to ensure that only authorized users and devices can access the appropriate resources at the appropriate time and for the appropriate purpose. IAM can involve various tasks or processes, such as authentication, authorization, provisioning, deprovisioning, auditing, or reporting. Automation can help to simplify and streamline these tasks or processes by using software tools or scripts that can execute predefined actions or workflows based on certain triggers or conditions. For example, automation can help to create, update, or delete user accounts in bulk based on a file or a database, rather than manually entering or modifying each account individually. The example in the question shows that an API is used to insert bulk access requests from a file into an identity management system. An API (Application Programming Interface) is a set of rules or specifications that defines how different software components or systems can communicate and exchange data with each other. An API can help to enable automation by providing a standardized and consistent way to access and manipulate data or functionality of a software component or system. The example in the question shows that an API is used to automate the process of inserting bulk access requests from a file into an identity management system, rather than manually entering each request one by one. The other options are not correct, as they describe different concepts or techniques. Command and control is a term that refers to the ability of an attacker to remotely control a compromised system or device, such as using malware or backdoors. Command and control is not related to what is described in the example. Data enrichment is a term that refers to the process of enhancing or augmenting existing data with additional information from external sources, such as adding demographic or behavioral attributes to customer profiles. Data enrichment is not related to what is described in the example. Single sign-on is a term that refers to an authentication method thatallows users to access multiple systems or applications with one set of credentials, such as using a single username and password for different websites or services. Single sign-on is not related to what is described in the example.

Incident response playbooksprovide a structuredstep-by-step guidefor handling security incidents. Theydefine actions to takewhen specificthreat indicators or eventsoccur, ensuring acoordinated and consistent response​.

Option A (Prioritizing business-critical assets)relates more todisaster recovery (DR)than incident response.

Option C (Documenting asset management)is part ofIT governance, not incident response.

Option D (Defining DR sites)falls underbusiness continuity planning, not real-time incident handling.

Thus,B is the best answer, asplaybooks are designed to trigger appropriate responses to incidents​.

Data loss prevention (DLP) is a tool that can prevent the exposure of PII outside of an organization by monitoring, detecting, and blocking sensitive data in motion, in use, or at rest.

Comprehensive Detailed Explanation:The nmap scan results show that Telnet (port 23) is open. Telnet transmits data, including credentials, in plaintext, which is insecure and should be disabled to enhance security. Here’s an explanation of each option:

A. Disable all protocols that do not use encryption

Explanation: Disabling unencrypted protocols (such as Telnet) reduces exposure to man-in-the-middle (MITM) attacks and credential sniffing. Telnet should be replaced with a secure protocol like SSH, which provides encryption for transmitted data.

B. Configure client certificates for domain services

Explanation: While client certificates enhance authentication security, they are more relevant to services like LDAP over SSL (port 636), which is already secure. This would not address the Telnet vulnerability.

C. Ensure that this system is behind a NGFW

Explanation: A Next-Generation Firewall (NGFW) provides enhanced network security, but it may not mitigate the risks of unencrypted protocols if they are allowed internally.

D. Deploy a publicly trusted root CA for secure websites

Explanation: Public root CAs are used for website authentication and encryption, relevant only if this system is hosting a publicly accessible HTTPS service. It would not impact Telnet security.

The Diamond Model of Intrusion Analysis focuses on understanding the relationships between the adversary, their capabilities, infrastructure, and victim. It provides a structured approach to examining how attackers exploit information assets. According to CompTIA CySA+, this model is valuable for detailing attack patterns and understanding the infrastructure attackers use. The other options, like Structured Threat Information Expression (A) and OWASP Testing Guide (B), address threat data sharing and web application testing, respectively, while the Open Source Security Testing Methodology Manual (OSSTMM) (C) covers general security testing procedures.

The best priority based on common attack frameworks for a new program to reduce attack surface risks and threats as part of a zero trust approach is to reduce the administrator and privileged access accounts. Administrator and privileged access accounts are accounts that have elevated permissions or capabilities to perform sensitive or critical tasks on systems or networks, such as installing software, changing configurations, accessing data, or granting access. Reducing the administrator and privileged access accounts can help minimize the attack surface, as it can limit the number of potential targets orentry points for attackers, as well as reduce the impact or damage of an attack if an account is compromised.

A risk score is a numerical value that represents the potential impact and likelihood of a vulnerability being exploited. It can help to identify the potential loss incurred by an issue and prioritize remediation efforts accordingly. https://www.comptia.org/training/books/cysa-cs0-003-study-guide

Server-Side Request Forgery (SSRF) occurs when an attacker manipulates a web server to make unauthorized internal or external requests, often to access internal resources or exfiltrate data.

A Web Application Firewall (WAF) is the best mitigation because it:

Filters and blocks malicious requests before they reach the server.

Prevents attackers from sending unauthorized requests to internal services.

Can detect and block SSRF patterns in incoming traffic.

Why Not Other Options?

B (CASB) → Used for cloud access control, not effective against SSRF.

C (Forward Proxy) → Helps with outbound traffic control, but SSRF involves incoming requests.

D (MFA) → Helps with authentication but does NOT prevent SSRF attacks.

Compensating controls are the best approach to minimize the risk of the outdated servers being compromised, as they can provide an alternative or additional layer of security when the primary control is not feasible or effective. Compensating controls are security measures that are implemented to mitigate the risk of a vulnerability or an attack when the primary control is not feasible or effective. For example, if the servers are running outdated operating systems and cannot be patched, a compensating control could be to isolate them from the rest of the network, or to implement a firewall or an intrusion prevention system to monitor and block any malicious traffic to or from the servers. Compensating controls can help reduce the likelihood or impact of an exploit, but they do not eliminate the risk completely. Therefore, the security analyst should also consider upgrading or replacing the outdated servers as soon as possible.

The correct answer is A. XML.

STIX and OpenloC are two standards for representing and exchanging cyber threat intelligence (CTI) information. STIX stands for Structured Threat Information Expression and OpenloC stands for Open Location and Identity Coordinates. Both standards use XML as the underlying data format to encode the information in a structured and machine-readable way. XML stands for Extensible Markup Language and it is a widely used standard for defining and exchanging data on the web. XML uses tags, attributes, and elements to describe the structure and meaning of the data. XML is also human-readable, as it uses plain text and follows a hierarchical and nested structure.

XML is not the only format that can be used to make STIX and OpenloC information readable by both humans and machines, but it is the most common and widely supported one. Other formats that can be used include JSON, CSV, or PDF, depending on the use case and the preferences of the information producers and consumers. However, XML has some advantages over other formats, such as:

XML is more expressive and flexible than JSON or CSV, as it can define complex data types, schemas, namespaces, and validation rules.

XML is more standardized and interoperable than PDF, as it can be easily parsed, transformed, validated, and queried by various tools and languages.

XML is more compatible with existing CTI standards and tools than other formats, as it is the basis for STIX 1.x, TAXII 1.x, MAEC, CybOX, OVAL, and others.

The hard disk is the piece of data that should be collected first in order to preserve sensitive information before isolating the server. The hard disk contains all the files and data stored on the server, which may include evidence of malicious activity, such as malware installation, data exfiltration, or configuration changes. The hard disk should be collected using proper forensic techniques, such as creating an image or a copy of the disk and maintaining its integrity using hashing algorithms.

XSS is a type of web application attack that exploits the vulnerability of a web server or browser to execute malicious scripts or commands on the client-side. XSS attackers inject malicious code, such as JavaScript, VBScript, HTML, or CSS, into a web page or application that is viewed by other users. The malicious code can then access or manipulate the user’s session, cookies, browser history, or personal information, or perform actions on behalf of the user, such as stealing credentials, redirecting to phishing sites, or installing malware12

The line in the web server log shows an example of an XSS attack using VBScript. The attacker tried to insert an tag with a malicious SRC attribute that contains a VBScript code. The VBScript code is intended to display a message box with the text “test” when the user views the web page or application. This is a simple and harmless example of XSS, but it could be used to test the vulnerability of the web server or browser, or to launch more sophisticated and harmful attacks3

Dynamic Application Security Testing (DAST) is used to detect vulnerabilities in running applications, including common issues like SQL injection, FRI, XSS, etc. It aligns with the goal of implementing security by design.

Wireshark is a network protocol analyzer that allows analysts to capture and inspect data packets traveling through a network. This makes it ideal for investigating unusual network activity, as it provides detailed insights into the nature and content of network traffic. In this case, Wireshark can help identify potentially malicious packets and understand the nature of the observed traffic. Options A (WAF) and C (EDR) are primarily used for monitoring and protecting web applications and endpoints, respectively, and Nmap (D) is typically used for network discovery and mapping, not detailed traffic analysis. According to CompTIA CySA+, packet analysis tools like Wireshark are invaluable for deep-dive investigations into network anomalies.

Exploit code maturity in the CVSS v.3.1 temporal metrics refers to the reliability and availability of exploit code for a vulnerability. Public availability of exploit code increases the exploit code maturity score.

The availability of exploit code affects the 'Exploit Code Maturity' metric in CVSS v.3.1. This metric evaluates the level of maturity of the exploit that targets the vulnerability. When exploit code is readily available, it suggests a higher level of maturity, indicating that the exploit is more reliable and easier to use.

ABusiness Impact Analysis (BIA)is the correct document thatidentifies critical servicesand definesRecovery Point Objectives (RPOs)andRecovery Time Objectives (RTOs). It helps organizations determine the impact of downtime and the maximum tolerable outages for business functions.

Disaster recovery plan (A)uses the information from the BIA.

Playbooks (C)are tactical and focus on specific incidents.

Backup plans (D)support BIA but don't define RPO/RTO themselves.

An incident response plan is a set of predefined procedures and guidelines that an organization follows when faced with a security breach or attack. An incident response plan helps to ensure that the organization can quickly and effectively contain, analyze, eradicate, and recover from the incident, as well as prevent or minimize the damage and impact to the business operations, reputation, andcustomers. An incident response plan also defines the roles and responsibilities of the incident response team, the communication channels and protocols, the escalation and reporting procedures, and the tools and resources available for the incident response.

By following the company’s incident response plan, the administrator can ensure that they are following the best practices and standards for handling a security incident, and that they are coordinating and collaborating with the relevant stakeholders and authorities. Following the company’s incident response plan can also help to avoid or reduce any legal, regulatory, or contractual liabilities or penalties that may arise from the incident.

The other options are not as effective or appropriate as following the company’s incident response plan. Informing the internal incident response team (A) is a good step, but it should be done according to the company’s incident response plan, which may specify who, when, how, and what to report. Reviewing the lessons learned for the best approach © is a good step, but it should be done after the incident has been resolved and closed, not during the active response phase. Determining when the access started (D) is a good step, but it should be done as part of the analysis phase of the incident response plan, not before following the plan.

CVSS 3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H is the attack vector that the analyst should remediate first, as it has the highest CVSSv3 score of 8.1. CVSSv3 (Common Vulnerability Scoring System version 3) is a standard framework for rating the severity of vulnerabilities, based on various metrics that reflect the characteristics and impact of the vulnerability. The CVSSv3 score is calculated from three groups of metrics: Base, Temporal, and Environmental. The Base metrics are mandatory and reflect the intrinsic qualities of the vulnerability, such as how it can be exploited, what privileges are required, and what impact it has on confidentiality, integrity, and availability. The Temporal metrics are optional and reflect the current state of the vulnerability, such as whether there is a known exploit, a patch, or a workaround. The Environmental metrics are also optional and reflect the context of the vulnerability in a specific environment, such as how it affects the asset value, security requirements, or mitigating controls. The Base metrics produce a score ranging from 0 to 10, which can then be modified by scoring the Temporal and Environmental metrics. A CVSS score is also represented as a vector string, a compressed textual representation of the values used to derive the score.

The attack vector in question has the following Base metrics:

Attack Vector (AV): Network (N). This means that the vulnerability can be exploited remotely over a network connection.

Attack Complexity (AC): Low (L). This means that the attack does not require any special conditions or changes to the configuration of the target system.

Privileges Required (PR): Low (L). This means that the attacker needs some privileges on the target system to exploit the vulnerability, such as user-level access.

User Interaction (UI): None (N). This means that the attack does not require any user action or involvement to succeed.

Scope (S): Unchanged (U). This means that the impact of the vulnerability is confined to the same security authority as the vulnerable component, such as an application or an operating system.

Confidentiality Impact ©: High (H). This means that the vulnerability results in a total loss of confidentiality, such as unauthorized disclosure of all data on the system.

Integrity Impact (I): High (H). This means that the vulnerability results in a total loss of integrity, such as unauthorized modification or deletion of all data on the system.

Availability Impact (A): High (H). This means that the vulnerability results in a total loss of availability, such as denial of service or system crash.

Using these metrics, we can calculate the Base score using this formula:

Base Score = Roundup(Minimum[(Impact + Exploitability), 10])

Where:

Impact = 6.42 x [1 - ((1 - Confidentiality) x (1 - Integrity) x (1 - Availability))]

Exploitability = 8.22 x Attack Vector x Attack Complexity x Privileges Required x User Interaction

Using this formula, we get:

Impact = 6.42 x [1 - ((1 - 0.56) x (1 - 0.56) x (1 - 0.56))] = 5.9

Exploitability = 8.22 x 0.85 x 0.77 x 0.62 x 0.85 = 2.8

Base Score = Roundup(Minimum[(5.9 + 2.8), 10]) = Roundup(8.7) = 8.8

Therefore, this attack vector has a Base score of 8.8, which is higher than any other option.

The other attack vectors have lower Base scores, as they have different values for some of the Base metrics:

CVSS:3.0/AV:P/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H has a Base score of 6.2, as it has a lower value for Attack Vector (Physical), which means that the vulnerability can only be exploited by having physical access to the target system.

CVSS:3.0/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H has a Base score of 7.4, as it has a lower value for Attack Vector (Adjacent Network), which means that the vulnerability can only be exploited by being on the same physical or logical network as the target system.

CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H has a Base score of 6.8, as it has a lower value for Attack Vector (Local), which means that the vulnerability can only be exploited by having local access to the target system, such as through a terminal or a command shell.

Determining the asset value of each system is the best action to perform first, as it helps to categorize and prioritize the systems based on the sensitivity of the data they host. The asset value is a measure of how important a system is to the organization, in terms of its financial, operational, or reputational impact. The asset value can help the security analyst to assign a risk level and a protection level to each system, and to allocate resources accordingly. The other actions are not as effective as determining the asset value, as they do not directly address the goal of promoting confidentiality, availability, and integrity of the data. Interviewing the users who access these systems may provide some insight into how the systems are used and what data they contain, but it may not reflect the actual value or sensitivity of the data from an organizational perspective. Scanning the systems to see which vulnerabilities currently exist may help to identify and remediate some security issues, but it does not help to categorize or prioritize the systems based on their data sensitivity. Configuring alerts for vendor-specific zero-day exploits may help to detect and respond to some emerging threats, but it does not help to protect the systems based on their data sensitivity.

The command in question involves an encoded PowerShell command, which is typically used by attackers to obfuscate malicious scripts. To decode and understand the payload, one would need to decode the base64 encoded string. This is why option A is the correct answer, as 'base64 -d' is a command used to decode data encoded with base64. This process will reveal the plaintext of the encoded command, which can then be analyzed to understand the actions that the attacker was attempting to perform. Option B is risky and not advised without a controlled and isolated environment. Option C is not safe because executing unknown or suspicious code with administrator privileges could cause harm to the system or network. Option D also poses a risk of executing potentially harmful code on an analyst’s workstation.

The suspicious line in the web server logs is an attempt to execute a command on the server, indicating a command injection attack.References: CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 5, page 197; CompTIA CySA+ CS0-003 Certification Study Guide, Chapter 5, page 205.

Abit-level imageis a forensic-grade copy that preservesalldata on a disk, including unallocated space, deleted files, and metadata. This is the most legally defensible form of digital evidence collection, as it ensures that no potential evidence is missed​.

Copying all access files (Option A)only captures live files and omits deleted or system-level artifacts that may be critical.

Creating a file-level archive (Option B)is insufficient because it does not capture system metadata or slack space where forensic artifacts reside.

Providing a full system backup inventory (Option C)may include important files, but it lacks forensic integrity because backups often modify timestamps and do not capture all system states​.

Thus, the correct answer isD, as abit-level image ensures forensic integrity and completeness of evidence​.

Step 1: Analyzing the SFTP Log

The SFTP log provides a record of file transfer and login activities:

User “sjames” logged in from several IP addresses:

192.168.10.32 and 192.168.10.37 (internal network IPs)

32.111.16.37 and 41.21.18.102 (external IPs)

We see file alterations in the /var/www directory, which is commonly the web directory.

Modified files: about_us.html, index.html

Suspicious activity:

192.168.11.102 and 41.21.18.102 modified the files.

32.111.16.37 had failed login attempts, indicating possible unauthorized access attempts.

The most suspicious IP here is 41.21.18.102, as it’s associated with direct file modifications, possibly indicating unauthorized access.

Step 2: Reviewing Netstat

The netstat output shows active connections and their states:

IP 41.21.18.102 has an ESTABLISHED connection with port 22, commonly used for SFTP.

IP 32.111.16.37 is also attempting connections, and 32.111.16.37 connections are in a TIME_WAIT state, showing prior connections were recently closed.

The netstat output reaffirms 41.21.18.102 is actively connected and potentially involved in malicious activities.

Step 3: Checking the HTTP Access Log

The HTTP Access log shows access to about_us.html:

32.111.16.37 repeatedly accessed /about_us.html with 404 errors, indicating attempts to reach non-existing pages.

41.21.18.102 accessed the 200 status code, showing successful page requests, but since this IP was modifying files directly on the server, it might be testing or verifying changes.

Again, 41.21.18.102 stands out as it matches both successful file modification and page request patterns, while 32.111.16.37 shows unsuccessful attempts.

Step 4: Selecting the IP of Concern

Based on the above analysis:

Answer: 41.21.18.102 should be the IP of concern due to its direct file modifications on critical web files (about_us.html, index.html).

Step 5: Identifying the Indicator of Compromise

Potential indicators include unauthorized file modifications:

Modified index.html file is the correct answer, as it indicates direct changes to website content and is often a clear sign of compromise.

Step 6: Selecting Corrective Actions

To mitigate and prevent further compromise:

Change the password on the “sjames” account: The account was used across various IPs, indicating potential account compromise.

Block external SFTP access: Restricting SFTP to internal IPs only would prevent unauthorized external modifications. Since 41.21.18.102 was external, this would stop similar threats.

Summary

IP of Concern: 41.21.18.102

Indicator of Compromise: Modified index.html file

Corrective Actions:

Change the password on the sjames account

Block external SFTP access

These selections address both the immediate security breach and implement a preventative measure against future unauthorized access.

In this scenario, the security analyst is presented with multiple vulnerabilities, including a critical zero-day vulnerability affecting the web server with a CVSS score of 10. The CVSS (Common Vulnerability Scoring System) provides a standardized method for rating IT vulnerabilities, with a score of 10 indicating the highest severity.

Option A:Contact the web systems administrator and request that they shut down the asset.

Correct Choice:Given the critical nature of a zero-day vulnerability with a CVSS score of 10, immediate action is warranted to prevent potential exploitation. Shutting down the affected web server reduces the attack surface and mitigates the risk until a patch or workaround is available. This aligns with incident response best practices, where containment is a priority to prevent further damage.

Option B:Monitor the patch releases for all items and escalate patching to the appropriate team.

Incorrect Choice:While monitoring for patches is essential, it is a reactive approach. In the case of a zero-day vulnerability with active exploitation potential, waiting for a patch without implementing immediate protective measures exposes the organization to significant risk.

Option C:Run the vulnerability scan again to verify the presence of the critical finding and the zero-day vulnerability in the environment.

Incorrect Choice:Re-scanning may confirm the vulnerability's presence but does not address the immediate threat. Action to mitigate the risk should take precedence over verification, especially when the vulnerability is known and critical.

Option D:Forward the advisory to the web security team and initiate the prioritization strategy for the other vulnerabilities.

Incorrect Choice:Communicating with the web security team is important; however, in the face of a critical zero-day vulnerability, immediate action (such as shutting down the affected asset) is necessary before addressing other vulnerabilities.

Asimulation(such as atabletop exercise or full-scale IR drill) is the best way to demonstrate real-world readiness without affecting operations​.

Option A (Reviewing lessons-learned and playbooks)is valuable but does not actively test readiness.

Option C (Deploying malware)is highly risky and unethical in a production environment.

Option D (Disaster recovery site testing)focuses on DR, not security incident readiness.

Thus,B is the best choice, as simulations effectivelytest incident response capabilities without operational disruption.

Fuzzing is a testing technique where invalid or random data is inputted into a system to find vulnerabilities, crashes, or unexpected behaviors. It’s commonly used in software security to identify flaws that could lead to security breaches. According to CompTIA’s CySA+ curriculum, fuzzing is a dynamic testing method for exposing application weaknesses. Options like static testing (B) involve analyzing code without execution, while reverse engineering (A) and debugging (D) involve different methodologies for understanding or fixing code, not intentionally stressing it.

This scenario describes a strictgovernance policyrequiring multiple approvals for high-risk security group changes.Organizational governancerefers to policies that enforce security controls and approval workflows​.

Option B (MOU - Memorandum of Understanding)refers to agreements between parties, not internal security processes.

Option C (SLA - Service Level Agreement)refers to service guarantees, not security governance.

Option D (Business process interruption)might be a consequence, but it is not the primaryinhibitor to remediationin this case.

Thus,A is correct, as governance rules are restricting remediation speed.

Indicators of compromise (IoCs) are pieces of data or evidence that suggest a system or network has been compromised by an attacker or malware. IoCs can include IP addresses, domain names, URLs, file hashes, registry keys, network traffic patterns, user behaviors, or system anomalies. IoCs can be used to detect, analyze, and respond to security incidents, as well as to share threat intelligence with other organizations or authorities. IoCs can produce the data needed for an executive briefing on possible threats to the organization, as they can provide information on the source, nature, scope, impact, and mitigation of the threats.

The scanner is running in active mode, which is the cause of this issue. Active mode is a type of vulnerability scanning that sends probes or requests to the target systems to test their responses and identify potential vulnerabilities. Active mode can provide more accurate and comprehensive results, but it can also cause more network traffic, performance degradation, or system instability. In some cases, active mode can trigger denial-of-service (DoS) conditions or crash the target systems, especially if they are not configured to handle the scanning requests or if they have underlying vulnerabilities that can be exploited by the scanner12. Therefore, the analyst should use caution when performing active mode scanning, and avoid scanning business-critical or sensitive systems without proper authorization and preparation3. References: Vulnerability Scanning for my Server - Spiceworks Community, Negative Impacts of Automated Vulnerability Scanners and How … - Acunetix, Vulnerability Scanning Best Practices

Isolation is the first step to take after detecting some indicators of compromise (IoCs) of possible ransomware contamination. Isolation prevents the ransomware from spreading to other servers or segments of the network, and allows the security team to investigate and contain the incident. Isolation can be done by disconnecting the infected servers from the network, blocking the malicious traffic, or applying firewall rules12.

Comprehensive and Detailed Step-by-Step Explanation:Automation in cybersecurity is best utilized to improve the speed and accuracy of incident detection, analysis, and response. Tools like SOAR (Security Orchestration, Automation, and Response) streamline workflows, allowing analysts to focus on more complex tasks while reducing response times. This ensures quicker containment and mitigation of threats.

XDR logs will confirm the malware infection because XDR is a system that collects and analyzes data from multiple sources, such as endpoints, networks, cloud applications, and email security, to detect and respond to advanced threats12. XDR can provide a comprehensive view of the attack chain and the context of the malware infection. Firewall logs, IDS logs, and MFA logs are not sufficient to confirm the malware infection, as they only provide partial or indirect information about the network traffic, intrusion attempts, or user authentication. References: Cybersecurity Analyst+ - CompTIA, XDR: definition and benefits for MSPs| WatchGuard Blog, Extended detection and response - Wikipedia

An Office document with a malicious macro was opened is the most likely explanation for the suspicious activity on the company laptop, as it reflects the common technique of using macros to execute PowerShell commands that download and run malware. A macro is a piece of code that canautomate tasks or perform actions in an Office document, such as a Word file or an Excel spreadsheet. Macros can be useful and legitimate, but they can also be abused by threat actors to deliver malware or perform malicious actions on the system. A malicious macro can be embedded in an Office document that is sent as an attachment in a phishing email or hosted on a compromised website. When the user opens the document, they may be prompted to enable macros or content, which will trigger the execution of the malicious code. The malicious macro can then use PowerShell, which is a scripting language and command-line shell that is built into Windows, to perform various tasks, such as downloading and running malware from a remote URL, bypassing security controls, or establishing persistence on the system. The log excerpt shows that PowerShell was used to download a string from a URL using the WebClient.DownloadString method, which is a common way to fetch and execute malicious code from the internet. The log also shows that PowerShell was used to invoke an expression (iex) that contains obfuscated code, which is another common way to evade detection and analysis. The other options are not as likely as an Office document with a malicious macro was opened, as they do not match the evidence in the log excerpt. A credential-stealing website was visited is possible, but it does not explain why PowerShell was used to download and execute code from a URL. A phishing link in an email was clicked is also possible, but it does not explain what happened after the link was clicked or how PowerShell was involved. A web browser vulnerability was exploited is unlikely, as it does not explain why PowerShell was used to download and execute code from a URL.

The best action for the incident response team to recommend in this scenario is to perform no action until HR or legal counsel advises on next steps. This action can help avoid any potential legal or ethical issues, such as violating employee privacy rights, contractual obligations, or organizational policies. This action can also help ensure that any evidence or information collected from the employee’s system or network is admissible and valid in case of any legal action or dispute. The incident response team should consult with HR or legal counsel before taking any action that may affect the employee’s system or network.

The correct answer is A. Implanted a backdoor.

A backdoor is a method that allows an unauthorized user to access a system or network without the permission or knowledge of the owner. A backdoor can be installed by exploiting a software vulnerability, by using malware, or by physically modifying the hardware or firmware of the device. A backdoor can be used for various malicious purposes, such as stealing data, installing malware, executing commands, or taking control of the system.

In this case, the consultant implanted a backdoor in the website by using an HTML and PHP code snippet that displays an image of a shutdown button and an alert message that says “Exit”. However, the code also echoes the remote address of the server, which means that it sends the IP address of the visitor to the attacker. This way, the attacker can identify and target the visitors of the website and use their IP addresses to launch further attacks or gain access to their devices.

The code snippet is an example of a clickjacking attack, which is a type of interface-based attack that tricks a user into clicking on a hidden or disguised element on a webpage. However, clickjacking is not the main goal of the consultant, but rather a means to implant the backdoor. Therefore, option C is incorrect.

Option B is also incorrect because privilege escalation is an attack technique that allows an attacker to gain higher or more permissions than they are supposed to have on a system or network. Privilege escalation can be achieved by exploiting a software vulnerability, by using malware, or by abusing misconfigurations or weak access controls. However, there is no evidence that the consultant implemented privilege escalation on the website or gained any elevated privileges.

Option D is also incorrect because patching is a process of applying updates to software to fix errors, improve performance, or enhance security. Patching can prevent or mitigate various types of attacks, such as exploits, malware infections, or denial-of-service attacks. However, there is no indication that the consultant patched the web server or improved its security in any way.

An incident response plan (IRP) is a document that defines the roles and responsibilities, procedures, and guidelines for responding to a security incident. It helps the security team to act quickly and effectively, minimizing the impact and cost of the incident. An IRP should specify who should conduct the next steps following a security event, such as containment, eradication, recovery, and analysis12. References: CompTIA CySA+ CS0-003 Certification Study Guide, page 362; 6 Incident Response Steps to Take After a Security Event, section 2.

A vulnerability scan report should include information about the affected hosts, such as their IP addresses, hostnames, operating systems, and services. It should also include a risk score for each vulnerability, which indicates the severity and potential impact of the vulnerability on the host and the organization. Official References: https://www.first.org/cvss/

Command-and-control (C2) beaconing involves compromised systems communicating with an attacker’s server at regular intervals, often using HTTPS to blend in with legitimate traffic. This is indicative of a potential compromise where malware communicates back to a command center. The persistent nature of the connections after hours and throughout the day suggests automated beaconing, which is a tell-tale sign of C2 activity. According to CompTIA CySA+, this type of activity should raise immediate suspicion and warrants further investigation and containment. While options B, C, D, and E might indicate other issues, they do not fit the pattern described as well as option A.

A HTTP/404 error code means that the requested page or resource was not found on the web server. This could be caused by various reasons, such as incorrect URLs, moved or deleted pages, missing assets, or server misconfigurations123. The analyst should first identify the source of the requests and examine the related activity to determine if they are legitimate or malicious, and what actions need to be taken to resolve the issue. The other options are either premature or irrelevant without further investigation. References: 1: 404 Page Not Found Error: What It Is and How to Fix It 2: 404 Error Code: What Causes Them and How To Fix It 3: About 404 errors and how to Troubleshoot it?

Thepost-incident review processhelps an organization identify gaps in its response and security posture. Assigning different departmental groups ensures that flaws inspecific work areas (such as IT, HR, or legal teams)are identified and addressed​.

Option Bis incorrect because not all staff need exposure; the review focuses on relevant stakeholders.

Option Cis a part of the process, but the main goal is improvement, not just playbook verification.

Option D(cross-training) is a benefit but not the main objective.

Thus,A is the best answerbecause it focuses on identifyingflaws in specific areas of incident management.

The first step should be to perform a public search for malware reports on taskhw.exe, as this file is suspicious for several reasons: it is located in a non-standard path, it has a high CPU usage, it is signed by an unknown entity, and it is only present on one host. A public search can help to determine if this file is a known malware or a legitimate program. If it is malware, the hunter can then take appropriate actions to remove it and prevent further damage. The other options are either premature or ineffective, as they do not provide enough information to assess the threat level of taskhw.exe. References: Cybersecurity Analyst+ - CompTIA, taskhw.exe Windows process - What is it? - file.net, Taskhostw.exe - What Is Taskhostw.exe & Is It Malware? - MalwareTips Forums

The next action that the CSIRT should conduct after isolating the compromised server from the network is to take a snapshot of the compromised server and verify its integrity. Taking a snapshot of the compromised server involves creating an exact copy or image of the server’s data and state at a specific point in time. Verifying its integrity involves ensuring that the snapshot has not been altered, corrupted, or tampered with during or after its creation. Taking a snapshot and verifying its integrity can help preserve and protect any evidence or information related to the incident, as well as prevent any tampering, contamination, or destruction of evidence.

Avoid is a risk management principle that describes the decision or action of not engaging in an activity or accepting a risk that is deemed too high or unacceptable. Avoiding a risk can eliminate the possibility or impact of the risk, as well as the need for any further risk management actions. In this case, the CISO decided the risk score would be too high and refused the software request. This indicates that the CISO selected the avoid principle for risk management.

A rollback had been executed on the instance. If a database server is restored to a previous state, it may reintroduce a vulnerability that was previously fixed. This can happen due to backup and recovery operations, configuration changes, or software updates. A rollback can undo the patching or mitigation actions that were applied to remediate the vulnerability. References: Vulnerability Remediation: It’s Not Just Patching, Section: The Remediation Process; Vulnerability assessment for SQL Server, Section: Remediation

An on-path attack is a type of man-in-the-middle attack where an attacker intercepts and modifies network traffic between two parties. In this case, someone with internal access may be performing an on-path attack by forcing users into port 80, which is used for HTTP communication, instead of port 443, which is used for HTTPS communication. This would allow the attacker to compromise the user accounts and access the company’s internal portal.

SOAR stands for security orchestration, automation, and response, which is a term that describes a set of tools, technologies, or platforms that can help streamline, standardize, and automate security operations and incident response processes and tasks. SOAR can help minimize human engagement and aid in process improvement in security operations by reducing manual work, human errors, response time, or complexity. SOAR can also help enhance collaboration, coordination, efficiency, or effectiveness of security operations and incident response teams.

Researching federal laws, regulatory compliance requirements, and organizational policies to document specific reporting SLAs is the best action to address the reporting issue. Reporting SLAs are service level agreements that specify the time frame and the format for notifying the relevant authorities and the affected individuals of a data breach. Reporting SLAs may vary depending on the type and severity of the breach, the type and location of the data, the industry and jurisdiction of the organization, and the internal policies of the organization. By researching and documenting the reporting SLAs for different scenarios, the organization can ensure that it complies with the legal and ethical obligations of data breach notification, and avoid any penalties, fines, or lawsuits that may result from failing to report a breach in a timely and appropriate manner12. References: When and how to report a breach: Data breach reporting best practices, Incident and Breach Management

The correct regular expression to match a GET request to this API endpoint is "https://10\.1\.2\.3/api\?id=\d+ ". This pattern checks for the specific URL with an id parameter that accepts integer values. The syntax \d+ matches one or more digits, which aligns with the requirement for a single integer argument. Other options either use incorrect syntax or do not accurately capture the expected URL format. Regular expressions are vital in filtering and identifying patterns in logs, as recommended by CompTIA Cybersecurity Analyst (CySA+) practices for threat hunting and log analysis.

An SLA (Service Level Agreement) is a contract or agreement between a service provider and a customer that defines the expected level of service, performance, quality, and availability of the service. An SLA also specifies the responsibilities, obligations, and penalties for both parties in case of non-compliance or breach of the agreement. An SLA can help organizations to ensure that their security services are delivered in a timely and effective manner, and that any security incidents or vulnerabilities are addressed and resolved within a specified time frame. An SLA can also help to establish clear communication, expectations, and accountability between the service provider and the customer12

An MOU (Memorandum of Understanding) is a document that expresses a mutual agreement or understanding between two or more parties on a common goal or objective. An MOU is not legally binding, but it can serve as a basis for future cooperation or collaboration. An MOU may not besuitable for requiring remediation of a known threat within a given time frame, as it does not have the same level of enforceability, specificity, or measurability as an SLA.

Best-effort patching is an informal and ad hoc approach to applying security patches or updates to systems or software. Best-effort patching does not follow any defined process, policy, or schedule, and relies on the availability and discretion of the system administrators or users. Best-effort patching may not be effective or efficient for requiring remediation of a known threat within a given time frame, as it does not guarantee that the patches are applied correctly, consistently, or promptly. Best-effort patching may also introduce new risks or vulnerabilities due to human error, compatibility issues, or lack of testing.

Organizational governance is the framework of rules, policies, procedures, and processes that guide and direct the activities and decisions of an organization. Organizational governance can help to establish the roles, responsibilities, and accountabilities of different stakeholders within the organization, as well as the goals, values, and principles that shape the organizational culture and behavior. Organizational governance can also help to ensure compliance with internal and external standards, regulations, and laws. Organizational governance may not be sufficient for requiring remediation of a known threat within a given time frame, as it does not specify the details or metrics of the service delivery or performance. Organizational governance may also vary depending on the size, structure, and nature of the organization.

OWASP ZAP (Zed Attack Proxy) is a tool recommended for quickly testing web applications for vulnerabilities, including SQL injection, path traversal, and cross-site scripting. It is an open-source web application security scanner that helps identify security issues in web applications during the development and testing phases.

The correct answer is A. 121.19.30.221.

Based on the log files and the organization’s priorities, the host that warrants additional investigation is 121.19.30.221, because it is the only host that accessed a file containing sensitive data and is not from the partner vendor’s range.

The log files show the following information:

The IP addresses of the hosts that accessed the web server

The date and time of the access

The file path of the requested resource

The number of bytes transferred

The organization’s priorities are:

Unauthorized data disclosure is more critical than denial of service attempts

Denial of service attempts are more important than ensuring vendor data access

According to these priorities, the most serious threat to the organization is unauthorized data disclosure, which occurs when sensitive, protected, or confidential data is copied, transmitted, viewed, stolen, altered, or used by an individual unauthorized to do so123. Therefore, the host that accessed a file containing sensitive data and is not from the partner vendor’s range poses the highest risk to the organization.

The file that contains sensitive data is /reports/2023/financials.pdf, as indicated by its name and path. This file was accessed by two hosts: 121.19.30.221 and 216.122.5.5. However, only 121.19.30.221 is not from the partner vendor’s range, which is 216.122.5.x. Therefore, 121.19.30.221 is a potential unauthorized data disclosure threat and warrants additional investigation.

The other hosts do not warrant additional investigation based on the log files and the organization’s priorities.

Host 134.17.188.5 accessed /index.html multiple times in a short period of time, which could indicate a denial of service attempt by flooding the web server with requests45. However, denial of service attempts are less critical than unauthorized data disclosure according to the organization’s priorities, and there is no evidence that this host succeeded in disrupting the web server’s normal operations.

Host 202.180.1582 accessed /images/logo.png once, which does not indicate any malicious activity or threat to the organization.

Host 216.122.5.5 accessed /reports/2023/financials.pdf once, which could indicate unauthorized data disclosure if it was not authorized to do so. However, this host is from the partner vendor’s range, which is required to have access to monthly reports and is the only external vendor with authorized access according to the organization’s requirements.

Therefore, based on the log files and the organization’s priorities, host 121.19.30.221 warrants additional investigation as it poses the highest risk of unauthorized data disclosure to the organization.