huntrule

Windows Registry Event Triggered by RedMimicry Winnti Playbook (HTMLHelp\data)

Alerts on Windows registry events targeting HKLM\SOFTWARE\Microsoft\HTMLHelp\data associated with the RedMimicry Winnti playbook.

FreeReviewedSigma · High · v1
Product
windows
Category
registry_event
Author
Alexander Rausch (SigmaHQ), DRL 1.1
Published
2020-06-24
Updated
2026-07-30
AnalysisDetection

ATT&CK techniques

Persistence → Defense Evasion

  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 Windows registry events where the target object path contains HKLM\SOFTWARE\Microsoft\HTMLHelp\data, indicating manipulation under the HTML Help data location. Attackers may use such persistence or defense-impairment related registry changes to influence system behavior. The detection relies on Windows registry event telemetry capturing the TargetObject value associated with the action.

Reporting behind it

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Malicious WDigest UseLogonCredential Enabled for Cleartext Credential Theft (via registry_set)
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Windows Registry Event Triggered by RedMimicry Winnti Playbook (HTMLHelp\data)
Pivot detection · T1112 · 9 related

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