huntrule

Windows: rundll32 Triggering comsvcs.dll MiniDump Against lsass.exe

Detects rundll32 invoking comsvcs.dll to dump lsass.exe via a MiniDump export.

FreeReviewedSigma · High · v2
Product
windows
Category
process_access
Author
Roberto Rodriguez (Cyb3rWard0g), OTR (Open Threat Research) (SigmaHQ), DRL 1.1
Published
2020-10-20
Updated
2026-07-31
AnalysisDetection

ATT&CK techniques

Cred Access

  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

  14. Impact

What it detects

This rule flags process access behavior where rundll32 loads comsvcs.dll and targets lsass.exe for a memory dump using the MiniDump export. Attackers may use this technique to extract credentials and secrets from the LSASS process while appearing as a legitimate system utility execution. The detection relies on process-access telemetry capturing the source process (rundll32), the target process (lsass.exe), and call-trace content indicating comsvcs.dll usage.

Reporting behind it

Related detections9 linkedT1003.001 — drag to rearrange
Malicious WDigest Credential Caching Enabled via Registry (via registry_set)
Malicious Credential Dumping via Mimikatz Sekurlsa Command
Malicious Mimikatz Sekurlsa Logonpasswords Credential Dump
Malicious LSASS Credential Dump via ProcDump (via process_creation)
Malicious LSASS Memory Dump via comsvcs.dll by Salt Typhoon
Malicious LSASS Dump via Process Access (via process_access)
Malicious LSASS Credential Dump with LSASSY - Process (via process_creation)
Malicious LSASS Credential Dump with LSASSY - Admin Share (via security)
Malicious Task Manager Used for LSASS Dump - Kernel (via security)
Windows: rundll32 Triggering comsvcs.dll MiniDump Against lsass.exe
Pivot detection · T1003.001 · 9 related

Changelog

v2
  1. v2
    Candidate ingested via manual entry.2026-07-31
  2. v1
    No changelog recorded for this version.2026-07-30

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