How to Preserve Forensic Evidence from a Compromised EC2 Instance
Which THREE actions should be taken when preserving forensic evidence from an EC2 instance during an incident? (Select THREE.)
Quick Answer
The answer is to create an EBS snapshot of the compromised EC2 instance, detach the instance from the network by modifying its security group, and then stop the instance to prevent further modification. These three actions are correct because they preserve the exact state of the volume at the time of the incident, including malicious files and logs, while isolating the instance from the network to prevent data tampering or lateral movement. Stopping the instance ensures the evidence remains static for offline forensic analysis, maintaining the chain of custody as recommended by AWS. On the AWS Certified Security Specialty SCS-C02 exam, this scenario tests your understanding of forensic evidence preservation in EC2, often appearing as a multi-select question where traps include rebooting the instance or taking a memory dump without isolation. A common memory tip is the “Stop, Snap, and Segregate” rule: stop the instance, snapshot the EBS volume, and segregate the network via security group changes.
⚠ Common exam trap
The SCS-C02 exam often tests the misconception that rebooting or terminating an instance is a safe containment step, but in forensic contexts these actions destroy volatile evidence and should be avoided until after memory and disk acquisition.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Create an EBS snapshot of all volumes.
Option B is correct because creating an EBS snapshot of all attached volumes captures a point-in-time, block-level copy of the instance's disk data (including the root volume) that can later be restored and analyzed without altering the original evidence. Option D is correct because volatile memory contains artifacts such as running processes, network connections, and encryption keys that are lost on shutdown, so capturing a memory dump with a tool like LiME preserves this critical evidence. Option E is correct because modifying the security group to remove inbound/outbound rules isolates the instance from the network, preventing further compromise or data exfiltration while keeping the instance running so volatile evidence remains intact. Option A is not appropriate because rebooting destroys volatile memory and can trigger anti-forensic behavior, and Option C is not appropriate because terminating the instance destroys the ephemeral storage and volatile state and may delete the very evidence needed for investigation.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Reboot the instance to clear any malicious processes.
Why it's wrong here
Rebooting clears volatile memory, destroying running processes, network connections and injected code that forensic capture depends on; evidence must be acquired from the live instance before any restart. It is tempting because rebooting often disrupts malware, which suits rapid containment when preservation is not the objective.
- ✓
Create an EBS snapshot of all volumes.
Why this is correct
An EBS snapshot captures a point-in-time, block-level copy of every attached volume, preserving disk artefacts such as logs, malware and deleted files without altering the running instance. It satisfies evidence preservation while keeping the original instance available for further collection.
- ✗
Terminate the instance to prevent further compromise.
Why it's wrong here
Termination destroys the instance's memory, attached instance store volumes and its network identity, eliminating evidence that cannot be recovered afterwards; the instance must be isolated and snapshotted instead. It is tempting because termination guarantees the attacker loses access, which suits confirmed compromises where containment outweighs investigation.
- ✓
Capture a memory dump using a tool like LiME.
Why this is correct
A memory dump captures volatile artefacts — running processes, injected code, encryption keys and network connections — that vanish on shutdown or reboot. LiME acquires RAM to external storage, satisfying preservation of evidence that disk snapshots alone cannot retain.
- ✓
Detach the instance from the network by modifying the security group.
Why this is correct
Modifying the security group isolates the instance from the network, blocking attacker command-and-control and further data exfiltration while leaving the instance running and its memory intact. This contains the incident without destroying volatile evidence needed for forensic analysis.
Go deeper
Related to this question
About these practice questions
Courseiva writes every SCS-C02 question from scratch — 1,205 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
Same concept, more angles
1 more way this is tested on SCS-C02
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. Which TWO steps are part of the forensic acquisition process for an EC2 instance suspected of being compromised?
hard- A.Stop the instance immediately to prevent further damage.
- B.Enable termination protection on the instance.
- C.Terminate the instance to ensure the threat is contained.
- ✓ D.Capture the instance's memory using a forensic tool.
- ✓ E.Create a snapshot of the root EBS volume.
Why D: Capturing the instance's memory using a forensic tool (such as LiME or F-Response) preserves volatile data—including running processes, network connections, and encryption keys—that would be lost if the instance were stopped or terminated. This is a critical step in the forensic acquisition process to gather evidence of compromise without altering the system state.
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This SCS-C02 practice question is part of Courseiva's free Amazon Web Services certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the SCS-C02 exam.