Malicious Print Spooler Child Process Execution via PrintNightmare (via process_creation)

PremiumReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
HuntRule
Published
2026-09-18
Updated
2026-09-18

ATT&CK techniques

Priv Esc
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Defense Evasion

  7. Cred Access

  8. Discovery

  9. Lateral Movement

  10. Collection

  11. C2

  12. Exfiltration

  13. Impact

What it detects

This rule detects the Windows print spooler service spawning command shells or scripting interpreters, a behavior consistent with exploitation of the PrintNightmare vulnerability CVE-2021-34527. Observed in Elastic Security Labs GOAD lab telemetry where spoolsv.exe launching unusual child processes indicates remote code execution as SYSTEM for privilege escalation.

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Pivot detection · T1068 · 9 related

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