Windows Registry: New Root CA or AuthRoot Certificates Added to Certificate Stores

Alerts on registry certificate-store writes adding new Root/CA/AuthRoot certificates as binary blobs.

FreeReviewedSigma · Medium · v1
Product
windows
Category
registry_set
Author
frack113 (SigmaHQ), DRL 1.1
Published
2022-04-04
Updated
2026-07-30

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 flags Windows Registry writes where the TargetObject path indicates Root, CA, or AuthRoot certificate stores under HKLM, HKCU policies/enterprise areas. Adding certificates to these stores can allow attackers to trust attacker-controlled keys, enabling code-signing and TLS trust abuse. It relies on registry set events with TargetObject paths for the certificate store locations and entries that end with \Blob containing binary certificate data.

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Windows Registry: New Root CA or AuthRoot Certificates Added to Certificate Stores
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.