CS0-003 Practice Test 4 — 10 Questions

Question 1

During incident response, a team isolates a host but needs to preserve volatile evidence. What should be done first?

Accepted Answer

Capture a memory dump. When a host is isolated during incident response, the first priority is to capture volatile data before it is lost. A memory dump preserves the contents of RAM, which includes running processes, network connections, open files, and encryption keys. This data is critical for forensic analysis and disappears when the system is powered off. Disconnecting the network (option B) is important but should follow memory capture because network activity is part of the volatile state.

Answer

Disconnect from the network

Answer

Reimage the hard drive

Answer

Reboot the system

Question 2

A DAST scan cannot reach authenticated pages of a web application and reports only public content findings. What should be configured? For control selection, Which control best addresses the stated weakness without hiding risk?

Accepted Answer

Authenticated scanning with a test account and session handling. DAST scanners require authenticated access to crawl and test pages behind login forms. By configuring authenticated scanning with a test account and session handling (e.g., using cookies or OAuth tokens), the scanner can traverse protected routes and detect vulnerabilities such as SQL injection or XSS on authenticated pages. This directly addresses the stated weakness without masking risk.

Answer

Disable all application authentication

Answer

Treat absence of findings as proof of security

Answer

Reduce the scan to only the landing page

Question 3

A vulnerability management team has identified a critical vulnerability with a CVSS score of 9.8. The vulnerability affects a public-facing web server that handles sensitive customer data. The team decides to apply a patch immediately without going through the normal patch testing cycle. What type of patching procedure is this?

Accepted Answer

Emergency patching. When a critical vulnerability is actively exploited or poses immediate risk, emergency patching procedures are used to expedite deployment without standard testing.

Answer

Rolling patch deployment

Answer

Patch compliance tracking

Answer

Standard patch management

Question 4

A security analyst reviews a Nessus scan result for a web server. The plugin output indicates a critical vulnerability with CVSS v3.1 base score 9.8. The CVSS vector is AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Which of the following best describes the attack complexity?

Accepted Answer

Low. In the CVSS vector, AC:L means Attack Complexity is Low, indicating no special conditions are required for exploitation.

Answer

Critical

Answer

Medium

Answer

High

Question 5

During a threat hunting exercise, an analyst creates a hypothesis that a threat actor may be using scheduled tasks for persistence. Which Windows registry key or log source should the analyst examine to confirm the hypothesis?

Accepted Answer

Review the Windows Security Event Log for event ID 4698 (scheduled task creation). Scheduled tasks are stored in the Windows Task Scheduler and can be viewed via schtasks.exe, but the registry also contains persistence mechanisms. However, scheduled tasks are not primarily stored in the registry; they are in %SystemRoot%\Tasks. Alternatively, the analyst can use the Task Scheduler API. But among the options, examining the 'HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Schedule' is not standard. Actually, the correct answer is to examine the Task Scheduler logs or the tasks folder. However, the question specifies registry key or log source. The best answer is to review the Windows Security Event Log for event ID 4698 (scheduled task creation).

Answer

Check the Run registry keys (HKLM\Software\Microsoft\Windows\CurrentVersion\Run)

Answer

Examine the System event log for driver loading events

Answer

Analyze the application event log for error messages

Question 6

An organization has experienced a data breach involving personal data of EU residents. Under GDPR, what is the maximum time frame within which the organization must notify the supervisory authority?

Accepted Answer

72 hours. GDPR Article 33 requires that data breaches be reported to the relevant supervisory authority within 72 hours of becoming aware of the breach, unless the breach is unlikely to result in a risk to individuals' rights and freedoms.

Answer

24 hours

Answer

7 days

Answer

48 hours

Question 7

An analyst is using AWS GuardDuty and sees a finding that an EC2 instance is communicating with a known command-and-control (C2) IP address. What type of alert is this?

Accepted Answer

Threat intelligence finding. GuardDuty detects threats based on known malicious IPs, so communication with a C2 IP is a security finding indicating a potential compromise.

Answer

CASB alert investigation

Answer

Vulnerability scan result

Answer

Cloud audit log analysis

Question 8

A SOC analyst reviews DNS telemetry and sees a workstation resolving hundreds of algorithmically generated domains at fixed intervals, with most responses returning NXDOMAIN. What evidence should the analyst prioritize to validate command-and-control beaconing? In the evidence source phase, Which evidence source best supports or refutes the detection?

Accepted Answer

Correlate DNS query logs with endpoint process and network connection telemetry. Correlating DNS query logs with endpoint process and network connection telemetry (Option D) provides direct evidence of command-and-control (C2) beaconing by linking the algorithmically generated domain (AGD) queries to a specific process initiating outbound connections. This cross-referencing validates whether the DNS activity is part of a malware's C2 channel, as legitimate applications rarely generate hundreds of NXDOMAIN responses at fixed intervals. The SOC analyst can confirm the detection by identifying the parent process (e.g., a suspicious executable) and matching its network connections to the queried domains.

Answer

Search only for successful HTTP 200 responses

Answer

Delete the host from the SIEM asset inventory

Answer

Block all DNS traffic from the subnet

Question 9

You are a senior incident responder for a large technology company. During a routine threat hunting exercise, you detect unusual network traffic from a Linux web server to an external IP address that is known to be associated with an advanced persistent threat (APT) group. The web server runs a custom PHP application and is not in the DMZ; instead, it's on the internal network serving a management dashboard. You have captured a memory dump of the web server and analyzed it with volatility. The output shows a suspicious process running with the name 'apache2' but with an invalid parent process (PID 1 is 'apache2' itself). Additionally, you find a kernel module loaded called 'hideproc.ko' that is not part of the standard kernel. The network connections show a reverse shell to the external IP. You need to determine the most effective containment and eradication strategy that minimizes data loss and maintains business continuity while preserving evidence for law enforcement involvement.

Accepted Answer

Isolate the web server from the network immediately, capture a full disk and memory image, then reimage the server from a trusted backup or OS image, and restore application data from a known clean backup.. The presence of a kernel rootkit ('hideproc.ko') and a reverse shell indicates deep, persistent compromise that cannot be cleaned by patching or scanning. Isolating the server preserves volatile evidence (memory, disk) for law enforcement, while reimaging from a trusted backup ensures complete removal of the attacker's foothold, minimizing data loss and restoring business continuity.

Answer

Revert the web server to a previous snapshot from before the suspected compromise date, then run a full antivirus scan on the restored system.

Answer

Perform a live forensic analysis of the PHP application logs and database to identify the specific vulnerability used, then apply a hotfix to the application code.

Answer

Block the external IP address at the firewall and block all outbound traffic from the web server except to specific internal IPs, then continue monitoring for other compromised hosts.

Question 10

A hospital's IT department has been receiving reports from nursing staff that the electronic medical record (EMR) system is responding slowly during peak hours. The network team has verified that the local area network is operating normally and there is no bandwidth congestion. The security analyst reviews the firewall logs and observes repeated outbound connections from the EMR server to an external IP address 198.51.100.23 on TCP port 443 at regular 5-minute intervals. Each connection transfers a small amount of data. The analyst also notes that the EMR server's antivirus software is up to date and no malware has been detected. The hospital's security policy requires that all outbound connections from critical servers be explicitly approved. Further investigation reveals that 198.51.100.23 is associated with a hosting provider in a foreign country. The analyst suspects a data exfiltration. Which of the following actions should the analyst take FIRST?

Accepted Answer

Capture and analyze the network traffic between the EMR server and the external IP.. The analyst must first confirm whether the outbound connections are actually exfiltrating data or are legitimate (e.g., software updates, license checks). Capturing and analyzing the network traffic (e.g., using tcpdump or Wireshark) allows the analyst to inspect the payload and determine the nature of the data being sent, which is a standard step in incident response before taking more disruptive actions.

Answer

Install a network-based intrusion detection system to monitor the server.

Answer

Isolate the EMR server from the network and run a full forensic analysis.

Answer

Block all outbound traffic from the EMR server to the internet immediately.