Suspicious Free Space Wipe via cipher.exe

PremiumReviewedSigma · Medium · v1
Product
windows
Category
process_creation
Author
HuntRule
Published
2026-09-11
Updated
2026-09-11

ATT&CK techniques

Impact
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Lateral Movement

  11. Collection

  12. C2

  13. Exfiltration

What it detects

This rule detects cipher.exe invoked with the /w switch to overwrite unallocated disk space, an anti-recovery action used by the fake AI-tool installer ransomware to prevent carving of deleted originals. Wiping free space alongside encryption inhibits data recovery and signals destructive intent on the host.

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Suspicious Free Space Wipe via cipher.exe
Pivot detection · T1490 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.