ECCouncil 212-89 (EC-Council Certified Incident Handler) Practice Test 39

Question 380

After technical restoration, responders document the weakness exposed by: A compromised Linux server runs a malicious cron job as root while the executing file has changed hashes repeatedly. Which long-term control would reduce exposure to this specific pattern?

  1. Restrict service creation and monitor changes to boot-time execution paths
  2. Rebuild the trusted scheduled-job baseline and check root access paths
  3. Audit privileged cron modifications and restrict write access to job directories
  4. Review cron entries, file histories and spawned command lines

Explanation

Correct Answer

C:

Change monitoring targets persistence rather than static hashes; the assurance measure is designed around why signature-only cleanup fails, rather than hiding the reported activity.

Incorrect Answers

A:

Baseline enforcement exposes stealthy persistence modifications; this serves whether startup configuration will reinfect the system, whereas the requested result is recurrence prevention involving why signature-only cleanup fails.

B:

Cleaning mutable files without fixing scheduler or privileges is insufficient; the case needs recurrence prevention addressing why signature-only cleanup fails; case recovery is not future-risk control.

D:

The scheduled execution pattern remains stable even when payload bytes rotate; for why signature-only cleanup fails, an investigation is not recurrence prevention; recurrence prevention remains necessary.

Question 381

Forensic review begins with this reported event: An application server begins mining cryptocurrency and generating high CPU usage from a newly deployed container image. Which evidence-based task answers the primary uncertainty?

  1. Sign and scan images and restrict unapproved registry sources
  2. Compare image provenance, running process tree and outbound mining-pool traffic
  3. Stop the offending container and restrict its egress while preserving metadata
  4. Correlate east-west SMB flow records with common payload hashes and process starts

Explanation

Correct Answer

B:

Container identity and runtime behavior establish whether the workload is compromised; that evidence directly tests the concern about whether a malicious image is responsible for compute abuse, rather than relying on a single unverified indicator.

Incorrect Answers

A:

Software supply-chain controls reduce malicious workload deployment; prevention is not incident verification in the decision about whether a malicious image is responsible for compute abuse.

C:

Containment stops resource theft without necessarily destroying the image evidence; when judging whether a malicious image is responsible for compute abuse, immediate protection does not substantiate findings; this is instead initial containment or preservation.

D:

Shared artifacts and spread timing distinguish propagation from independent alerts; the relevant condition for that step is whether a worm propagated laterally, which is not shown for whether a malicious image is responsible for compute abuse.

Question 382

A technical closure review begins after this incident: Ransomware starts encrypting a file share while snapshots remain healthy and accessible. After the immediate situation is stabilized, what addresses the enabling failure?

  1. Use least-privilege share access and immutable backup protection
  2. Disconnect the infected client and revoke its write access to the share
  3. Rebuild affected hosts and restore files from verified preinfection backups
  4. Correlate file rename bursts with the initiating process and SMB session
  5. Rebuild the trusted scheduled-job baseline and check root access paths

Explanation

Correct Answer

C:

A clean source is required before trusted data restoration; it is the corrective action needed for which containment step stops ongoing encryption after the immediate hazard is controlled.

Incorrect Answers

A:

Reduced write permissions and protected copies limit future losses; for which containment step stops ongoing encryption, future hardening is not current-state recovery; trusted restoration remains necessary.

B:

Stopping the active writer limits damage while preserving clean snapshots; the requirement concerns which containment step stops ongoing encryption, so temporary protection does not complete correction.

D:

Identifying the source host helps stop active write activity; verification is not the corrective step in the decision about which containment step stops ongoing encryption.

E:

Cleaning mutable files without fixing scheduler or privileges is insufficient; the other incident centers on why signature-only cleanup fails, not this trusted restoration question about which containment step stops ongoing encryption.

Question 383

The incident is resolved, but its root weakness still requires policy attention: A malicious binary uses a trusted signed application to load a sidecar library from a writable directory. What durable process or monitoring change would make a repeat less likely?

  1. Detect unusual NXDOMAIN bursts and rare-domain patterns
  2. Control executable search paths and monitor unsigned modules in sensitive applications
  3. Replace altered components and fix writable library paths
  4. Alert on unusual scheduled-task registration by non-administrative workflows
  5. Examine module-load telemetry, library path and file creation times
  6. Quarantine the tampered application directory and block execution of the sidecar module

Explanation

Correct Answer

B:

Reducing side-loading opportunities makes abuse harder; it makes the lesson about whether DLL side-loading caused the activity part of normal operations.

Incorrect Answers

A:

Behavioral rules can catch domain rotation without static block lists; this serves whether the host exhibits domain-generation command traffic, whereas the requested result is recurrence prevention involving whether DLL side-loading caused the activity.

C:

Cleaning only the signed executable misses the malicious dependency; the goal is recurrence prevention for whether DLL side-loading caused the activity. Case recovery is not future-risk control.

D:

Monitoring persistence changes provides earlier detection; the other incident centers on which persistence artifact causes recurring execution, not this recurrence prevention question about whether DLL side-loading caused the activity.

E:

A legitimate executable can load a malicious library from an unsafe search location; the case needs recurrence prevention addressing whether DLL side-loading caused the activity; an investigation is not recurrence prevention.

F:

Containing the loading path prevents repeated execution without blaming the signer alone; when judging whether DLL side-loading caused the activity, one-time protection is not durable prevention; this is instead initial containment or preservation.

Question 384

The response record begins with an unresolved observation: The incident team stores a decryption key only inside the infected server's local password vault. What documentation or telemetry would most reliably support the incident determination?

  1. Validate that a clean recovery environment can retrieve the protected key
  2. Test authorized access to recovery material with the server disconnected
  3. Maintain offline escrow and periodic key-recovery exercises
  4. Review EDR event retention, log export and investigation access settings
  5. Secure an authorized independent copy of the recovery key under dual control

Explanation

Correct Answer

B:

A credential trapped on compromised infrastructure is not a usable emergency recovery asset; the objective is to establish whether recovery keys remain accessible during host isolation; the result can then guide the later protective decision.

Incorrect Answers

A:

Access testing catches dependency failure before an emergency; the case needs evidence validation addressing whether recovery keys remain accessible during host isolation; recovery is not factual verification.

C:

Resilience depends on accessible, well-governed cryptographic material; for whether recovery keys remain accessible during host isolation, prevention is not incident verification; evidence validation remains necessary.

D:

Insufficient history can hide the initial payload and lateral movement; that method could help with whether malware telemetry will survive delayed discovery; the evidence validation decision here involves whether recovery keys remain accessible during host isolation.

E:

Off-host custody permits restoration without relying on the infected machine; the goal is evidence validation for whether recovery keys remain accessible during host isolation. Immediate protection does not substantiate findings.

Question 385

The responder must establish the timeline from this observation: An endpoint's network isolation is reversed automatically by an unapproved management script. Which analysis step best addresses the missing confirmation?

  1. Suspend the conflicting automation and apply an authorized network quarantine
  2. Test incident overrides against routine endpoint management jobs
  3. Compare firewall and EDR isolation changes against automation run histories
  4. Inspect service-account tokens, credential use and database audit logs

Explanation

Correct Answer

C:

Control-plane conflict can reopen communication after responders block it; that evidence directly tests the concern about why malware containment does not persist, rather than relying on a single unverified indicator.

Incorrect Answers

A:

Isolation must remain effective while active compromise is investigated; the requirement concerns why malware containment does not persist, so immediate protection does not substantiate findings.

B:

Runbook integration prevents accidental de-isolation; the goal is evidence validation for why malware containment does not persist. Prevention is not incident verification.

D:

File deletion does not invalidate previously stolen credentials or sessions; the relevant condition for that step is which access path remains dangerous, which is not shown for why malware containment does not persist.

Question 386

The owner must verify the return to a trusted state for the following: A ransomware affiliate disables volume shadow copies just before encrypting departmental data. What corrective work is needed before routine operations resume?

  1. Rebuild affected systems and recover from protected backups verified clean
  2. Alert on unauthorized backup deletion and maintain immutable offline copies
  3. Rebuild affected hosts and restore files from verified preinfection backups
  4. Terminate the offending execution and secure isolated recovery repositories

Explanation

Correct Answer

A:

Local shadow copies may be unavailable or untrustworthy; the affected workflow should not be considered trusted until the issue of whether backup-suppression activity is part of the attack is resolved.

Incorrect Answers

B:

Protection outside attacker control improves recoverability; when judging whether backup-suppression activity is part of the attack, future hardening is not current-state recovery; this is instead recurrence prevention.

C:

A clean source is required before trusted data restoration; this serves which containment step stops ongoing encryption, whereas the requested result is trusted restoration involving whether backup-suppression activity is part of the attack.

D:

Protecting remaining copies is crucial before broader restoration; the requirement concerns whether backup-suppression activity is part of the attack, so temporary protection does not complete correction.

Question 387

Service owners need a bounded short-term safeguard after observing: A user downloads an executable from a spoofed update pop-up despite corporate patch management. What immediate action addresses the active exposure and leaves evidence available?

  1. Remove the installer and temporarily prevent execution of similar unapproved binaries
  2. Rebuild or cleanse impacted devices and restore trusted update channels
  3. Review download origin, browser events and installer signature information
  4. Disable unauthorized macro execution and quarantine the offending attachment

Explanation

Correct Answer

A:

Execution control stops subsequent users from running the same payload; this is a first-response safeguard for why user-driven fake updates bypassed approved channels, not a substitute for full root-cause analysis.

Incorrect Answers

B:

Recovery must distinguish the malicious installer from authorized patches; corrective follow-through follows initial protection in the decision about why user-driven fake updates bypassed approved channels.

C:

An untrusted web installer differs from centrally managed software distribution; the case needs initial containment or preservation addressing why user-driven fake updates bypassed approved channels; investigation alone does not control current conditions.

D:

Control prevents additional users from invoking the same script; the relevant condition for that step is whether document execution controls are effective, which is not shown for why user-driven fake updates bypassed approved channels.

Question 388

Cleanup is not considered complete. The case record describes: A server is restored from a snapshot taken after the initial compromise but before encryption. Which remediation task is necessary rather than merely suppressing the visible symptom?

  1. Restore the database from a verified clean recovery point and reconcile business transactions
  2. Record infection timelines and periodically test restore-point integrity
  3. Do not reconnect the restored image until it is investigated in isolation
  4. Choose a verified clean restore point and apply missing security fixes

Explanation

Correct Answer

D:

Trusted recovery requires both clean data and closed entry paths; technical closure should demonstrate that the control gap behind whether a backup predates attacker persistence is actually corrected.

Incorrect Answers

A:

Transaction-level reconciliation and a trustworthy recovery point address integrity failures beyond ransomware-note removal; the relevant condition for that step is whether business service recovery is complete, which is not shown for whether a backup predates attacker persistence.

B:

Backup selection improves when detection history is available; when judging whether a backup predates attacker persistence, future hardening is not current-state recovery; this is instead recurrence prevention.

C:

A latent backdoor can reactivate on an apparently recovered server; for whether a backup predates attacker persistence, temporary protection does not complete correction; trusted restoration remains necessary.

Question 389

The responder must establish the timeline from this observation: A hospital runs a malware drill but lacks clean images and emergency isolation plans for radiology workstations. Which analysis step best addresses the missing confirmation?

  1. Maintain manufacturer-approved recovery kits and clinical response exercises
  2. Review recovery images, clinical downtime procedures and network isolation dependencies
  3. Coordinate isolation decisions with clinical safety owners and segment affected devices
  4. Inventory isolated sandbox capacity and access to safe forensic tooling

Explanation

Correct Answer

B:

Medical device availability and supported reimaging constraints change the response options; for this investigation, the relevant uncertainty is whether malware response preparation covers critical medical endpoints, so independent confirmation matters.

Incorrect Answers

A:

Pretested procedures reduce operational risk during outbreaks; the requirement concerns whether malware response preparation covers critical medical endpoints, so prevention is not incident verification.

C:

Patient-care continuity must be considered alongside attack containment; immediate protection does not substantiate findings in the decision about whether malware response preparation covers critical medical endpoints.

D:

Untrusted code should be examined in a controlled environment that cannot reach business systems; that method could help with whether malware analysis has appropriate isolation; the evidence validation decision here involves whether malware response preparation covers critical medical endpoints.

Question 390

The coordinator needs corrective action rather than another alert. The event was: A domain controller records privileged authentication from a compromised workstation followed by remote service creation. Which follow-through step verifies the weakness was removed?

  1. Disable the implicated privileged sessions and isolate both source and target
  2. Rotate affected credentials and remove unauthorized services after forensic collection
  3. Remove unauthorized remote-access persistence and reset impacted credentials
  4. Use tiered administration and remote-service creation monitoring

Explanation

Correct Answer

B:

Restoration requires removal of both access and persistence; the affected workflow should not be considered trusted until the issue of whether stolen credentials enabled lateral movement is resolved.

Incorrect Answers

A:

Containing identities and endpoints stops further remote execution paths; the goal is trusted restoration for whether stolen credentials enabled lateral movement. Temporary protection does not complete correction.

C:

Cleanup should follow the actor's access mechanism, not simply delete OS utilities; the relevant condition for that step is whether living-off-the-land execution masks malicious behavior, which is not shown for whether stolen credentials enabled lateral movement.

D:

Separation of privileged use limits credential theft blast radius; when judging whether stolen credentials enabled lateral movement, future hardening is not current-state recovery; this is instead recurrence prevention.

EC-Council Certified Incident Handler (212-89) Practice Tests