CHFI Incident Response and First Responder Skills — 10 Questions

Question 1

An analyst receives an alert indicating a suspicious process (PID 3342) is making outbound connections on port 443 to an unknown IP. The system is a Windows 10 workstation. Which first responder action is MOST appropriate?

Accepted Answer

Capture a full memory dump using a tool like FTK Imager (Memory Capture) or DumpIt.. Capturing a full memory dump (option A) is the most appropriate first responder action because it preserves the volatile state of the suspicious process (PID 3342) and its associated artifacts (e.g., network connections, loaded DLLs, encryption keys) before any further system changes occur. This allows forensic analysis to identify the malware's behavior, such as command-and-control (C2) communication over port 443 (HTTPS), without altering evidence. Tools like FTK Imager (Memory Capture) or DumpIt acquire a raw .mem file that can be analyzed with Volatility or Rekall to extract process details, network sockets, and injected code.

Answer

Immediately disconnect the system from the network to contain the threat.

Answer

Check the Windows Event Logs for related entries.

Answer

Reboot the system to clear any malicious processes from memory.

Question 2

A security team suspects a data breach via an external attacker. The incident response plan requires preservation of evidence for legal proceedings. Which order of volatility should the first responder follow?

Accepted Answer

Capture memory, record network connections, acquire disk image, then collect backups.. Option C is correct because the order of volatility (OOV) dictates that the most volatile data (memory/registers) must be captured first, followed by network connections, then disk images, and finally backups. This sequence minimizes data loss and ensures evidence integrity for legal proceedings, as volatile data is lost when power is removed.

Answer

Capture disk image, then memory, then network connections.

Answer

Record network connections, capture disk image, then memory.

Answer

Collect backups first, then disk image, then memory.

Question 3

During an incident response, a first responder needs to collect evidence from a Linux server that is still running. The server has sensitive data and cannot be shut down. Which technique is BEST for acquiring a forensic image of the hard disk?

Accepted Answer

Use dd if=/dev/sda of=/mnt/evidence/image.dd bs=4M. Option B is correct because it uses dd with a 4M block size, which improves acquisition speed while still producing a bit-for-bit forensic image of the entire disk (/dev/sda). The conv=noerror,sync option in A is unnecessary for a live acquisition from a healthy disk and can mask read errors, while B's larger block size is more efficient for imaging a running system without shutdown.

Answer

Use dd if=/dev/sda of=/mnt/evidence/image.dd conv=noerror,sync

Answer

Use dd if=/dev/mapper/root of=/mnt/evidence/image.dd

Answer

Use dd if=/dev/sda1 of=/mnt/evidence/image.dd

Question 4

A first responder arrives at a scene where a computer is powered on and a user is logged in. An incident is suspected. What should the responder do FIRST?

Accepted Answer

Photograph the screen to document the current state.. Option C is correct because the first priority at a live incident scene is to preserve volatile evidence. Photographing the screen captures the current state of the system, including open applications, network connections, and user activity, which can be lost if the system is altered or powered down. This documentation provides a baseline for the investigation and ensures that critical volatile data is recorded before any forensic acquisition begins.

Answer

Begin capturing a memory dump using a forensic tool.

Answer

Power off the computer immediately to preserve the disk.

Answer

Ask the user to log off so the system can be imaged.

Question 5

You are responding to a suspected malware infection on a Windows 10 system. The system is still running. Which of the following should you collect FIRST?

Accepted Answer

Acquire a memory dump using a tool like WinPmem.. When a system is still running and suspected of malware infection, the first priority is to capture volatile data, which includes the contents of RAM. WinPmem is a tool designed to acquire a memory dump from a live Windows system, preserving critical evidence such as running processes, network connections, and injected code that would be lost on shutdown. This follows the order of volatility (RFC 3227), which mandates collecting memory before any non-volatile data like logs, registry, or disk images.

Answer

Collect the Windows Event Logs.

Answer

Export the contents of the Windows Registry.

Answer

Create a forensic image of the hard drive.

Question 6

During an incident response, a first responder needs to preserve the integrity of evidence. Which action ensures the best chain of custody?

Accepted Answer

Compute a SHA-256 hash of the acquired image immediately after collection and record it in the chain of custody form.. Option B is correct because computing a SHA-256 hash immediately after acquisition creates a cryptographic fingerprint of the image. This hash, when recorded in the chain of custody form, provides verifiable integrity: any subsequent alteration of the image will produce a different hash, proving tampering. While other steps are important, only hashing directly ties the evidence's integrity to a mathematical proof that can be independently verified later.

Answer

Use a write blocker when acquiring the disk image.

Answer

Document every person who handled the evidence.

Answer

Place the evidence in an evidence bag and lock it in a secure room.

Question 7

A first responder is called to investigate a potential insider threat. The suspect's computer is turned off. What is the BEST procedure?

Accepted Answer

Seize the computer and transport it to a forensic lab for imaging.. When a suspect's computer is already turned off, the best procedure is to seize it and transport it to a forensic lab for imaging. This preserves the integrity of the evidence by preventing any accidental modification of the hard drive's contents, which could occur if the system is powered on or booted from a live CD. In forensic best practices, the first responder should never boot a suspect's computer, as doing so can alter critical system files, timestamps, and volatile data, compromising the chain of custody and admissibility of evidence.

Answer

Compute a hash of the hard drive using a live CD.

Answer

Check the power cord and peripherals for tampering.

Answer

Turn on the computer to see if it boots normally.

Question 8

A first responder is responding to a ransomware incident on a Windows server. Which TWO actions should be performed to preserve evidence? (Choose two.)

Accepted Answer

Power off the server to prevent further data encryption.. Option B is correct because powering off the server preserves the encrypted state of the disk and prevents the ransomware from continuing to encrypt additional files or communicate with its command-and-control server. In a ransomware incident, immediate shutdown halts the encryption process and preserves the volatile evidence on disk, such as the ransomware binary and encrypted files, for forensic analysis.

Answer

Run an antivirus scan to remove the ransomware.

Answer

Restore the system from backup to minimize downtime.

Answer

Disconnect the network cable immediately.

Question 9

During the initial response to a suspected data exfiltration, which THREE pieces of volatile data should be collected first? (Choose three.)

Accepted Answer

Current network connections.. Current network connections (A) are volatile because they show active communication channels that could indicate data exfiltration in progress. If the system is shut down or disconnected, this evidence is lost immediately, making it a top priority for collection during initial response.

Answer

Windows registry hives.

Answer

Forensic image of the hard drive.

Question 10

Refer to the exhibit. A first responder runs netstat -ano on a Windows system. Which connection is MOST likely indicative of a potential C2 communication?

Accepted Answer

TCP 192.168.1.10:49153 to 203.0.113.50:443 TIME_WAIT PID 1204. Option C is correct because the connection from a high ephemeral port (49153) to an external IP (203.0.113.50) over HTTPS (port 443) with a short-lived TIME_WAIT state is a classic indicator of potential C2 beaconing. C2 communications often use HTTPS to blend with legitimate traffic, and the TIME_WAIT state suggests brief, periodic connections typical of beaconing, rather than sustained data transfer. The external IP is also in a documentation/test range (203.0.113.0/24), which is commonly used for examples but in a real scenario would be suspicious as an unknown external destination.

Answer

TCP 0.0.0.0:3389 LISTENING PID 668

Answer

TCP 192.168.1.10:49154 to 192.168.1.1:53 TIME_WAIT PID 2016

Answer

TCP 192.168.1.10:49152 to 10.0.0.5:80 ESTABLISHED PID 3342