huntrule

Windows Registry: Set LSA NoLMHash to 0 to Enable LM Hash Storage

Flags changes to NoLMHash (DWORD 0) enabling Windows to store LM password hashes.

FreeReviewedSigma · High · v1
Product
windows
Category
registry_set
Author
Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2023-12-15
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 alerts when the LSA registry setting "NoLMHash" is changed to DWORD 0, which allows Windows to store LAN Manager (LM) password hashes in Active Directory and local SAM databases. Enabling LM hash storage can weaken password hash protections and increase the exposure of credentials if those hashes are later accessed. It relies on Windows registry set telemetry capturing the modified value path and the specific DWORD data of 0.

Reporting behind it

Related detections9 linkedT1112 — drag to rearrange
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Malicious WDigest Credential Caching Enabled via Registry (via registry_set)
Suspicious Remote Desktop Enabled via fDenyTSConnections Registry by Sandworm
Malicious Gh0stBins RAT Registry Marker HHClient
Suspicious PebbleDash C2 Configuration Stored Under WMI Security Key (via registry_set)
Suspicious WDigest UseLogonCredential Enablement for Plaintext Credential Theft (via registry_set)
Windows Registry: Set LSA NoLMHash to 0 to Enable LM Hash Storage
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.