hardMultiple Choice
CISM Practice Question: An incident response team is dealing with a…
An incident response team is dealing with a persistent threat that uses fileless malware. Which containment strategy is most effective?
⚠ Common exam trap
CISM often tests the misconception that reimaging or disabling accounts is sufficient for fileless malware, ignoring the need to preserve volatile memory for analysis.
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
✓
Isolate affected endpoints from the network while preserving memory
Fileless malware resides in memory and often uses legitimate system tools, making traditional disk-based containment ineffective. Isolating affected endpoints from the network while preserving memory is most effective because it prevents lateral movement and exfiltration while allowing forensic analysis of volatile data to understand the attack.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Isolate affected endpoints from the network while preserving memory
Why this is correct
Fileless malware resides in memory rather than on disk, so powering off destroys the only evidence. Isolating endpoints from the network halts propagation while preserving volatile memory for forensic analysis, satisfying containment without losing the artefacts needed to understand the threat.
- ✗
Disable user accounts
Why it's wrong here
Disabling user accounts severs credential-based access but does not stop an already-running in-memory payload or its network channel. Disabling accounts is tempting because it is fast and reversible, and it is correct when the compromise stems from stolen or misused credentials rather than code execution.
- ✗
Block known malicious IPs
Why it's wrong here
Fileless malware executes in memory and often beacons over ordinary HTTPS to rotating or compromised hosts, so IP blocklists miss the actual execution mechanism. Blocking known malicious IPs is tempting because it is quick and low-impact, and it suits commodity malware with fixed command-and-control infrastructure.
- ✗
Reimage all endpoints
Why it's wrong here
Reimaging removes on-disk persistence but fileless malware lives in memory and reinfects through the original entry vector, so endpoints return compromised. Reimaging is tempting because it guarantees clean state, and it is the right choice when malware has established deep on-disk persistence or the host is unrecoverable.
Go deeper
Related to this question
About these practice questions
This CISM question is part of Courseiva's 924-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official ISACA exam blueprint
This CISM practice question is part of Courseiva's free ISACA 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 CISM exam.