Free Practice Questions for CompTIA CS0-003 Exam

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.

Tocapture and analyze network traffic, the two best tools are:

tcpdump (Option A)– A command-line packet capture tool used for network traffic analysis.

Wireshark (Option D)– A GUI-based network packet analysis tool that provides deep inspection capabilities​.

Option B (SIEM)is forlog aggregationand does notcapturetraffic.

Option C (Vulnerability scanner)identifies weaknesses but does notcapturenetwork traffic.

Option E (Nmap)is used for network discovery and port scanning, not capturing traffic.

Option F (SOAR)automates security processes but does not capture traffic.

Thus,A (tcpdump) and D (Wireshark) are correct, asthey are the best tools for capturing and analyzing anomalous network traffic​.

Key Performance Indicators (KPIs)track the effectiveness of a security program, providing measurable insights intovulnerability detection, patching efficiency, and risk reduction. This makes KPIs ideal for executive dashboards​.

Option B (MOU - Memorandum of Understanding)refers toagreements between parties, not performance tracking.

Option C (SLO - Service Level Objective)defines operationaltargetsbut is nota tracking metric.

Option D (SLA - Service Level Agreement)defines expectations betweenservice providers and clients, not security metrics.

Thus,A (KPI) is the correct answer, asKPIs provide actionable insights into security effectiveness​.

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.

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.

The next step in the remediation process after applying a software patch is validation. Validation is a process that involves verifying that the patch has been successfully applied, that it has fixed the vulnerability, and that it has not caused any adverse effects on the system or application functionality or performance. Validation can be done using various methods, such as scanning, testing, monitoring, or auditing.

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.

Comprehensive and Detailed Step-by-Step Explanation:Directory traversal, also known as path traversal, is an attack that allows attackers to access restricted directories and execute commands outside the web server's root directory. The %2E encoding corresponds to a dot (.) in ASCII, and %2E%2E resolves to ../. The log entries indicate attempts to navigate directories upward to access sensitive files like /etc/passwd. Since no malicious activity was flagged, it is inferred this was either an unsuccessful or reconnaissance attempt.

The output shows that port 80 is open and running an HTTP service, indicating that the host could potentially be vulnerable to web-based attacks. The other options are not relevant for this purpose: the host is responsive to the ICMP request, as shown by the “Host is up” message; the host is not running a mail server, as there is no SMTP or POP3 service detected; the host is not allowing unsecured FTP connections, as there is no FTP service detected.References: According to the CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition123, one of the objectives for the exam is to “use appropriate tools and methods to manage, prioritize and respond to attacks and vulnerabilities”. The book also covers the usage and syntax of nmap, a popular network scanning tool, in chapter 5. Specifically, it explains the meaning and function of each option in nmap, such as “-sV” for version detection2, page 195. Therefore, this is a reliable source to verify the answer to the question.

Log entry 4 shows an attempt to exploit the zero-day command injection vulnerability by appending a malicious command (;cat /etc/passwd) to the end of a legitimate request (/cgi-bin/index.cgi?name=John). This command would try to read the contents of the /etc/passwd file, which contains user account information, and could lead to further compromise of the system. The other log entries do not show any signs of command injection, as they do not contain any special characters or commands that could alter the intended behavior of the application. Official References:

https://www.imperva.com/learn/application-security/command-injection/

https://www.zerodayinitiative.com/advisories/published/