huntrule

Malicious WmRAT Persistence via vcswin Run Key (via registry_set)

PremiumReviewedSigma · High · v1
Product
windows
Category
registry_set
Author
HuntRule
Published
2026-09-16
Updated
2026-09-16
AnalysisDetection

ATT&CK techniques

Persistence → Priv Esc

  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 detects a Run key value pointing to vcswin.exe, the persistence executable Bitter APT dropped in ProgramData to relaunch WmRAT at logon. The autostart entry references an attacker-staged binary rather than a legitimate application. A Run value pointing to vcswin.exe is a strong persistence indicator.

Reporting behind it

Related detections9 linkedT1547.001 — drag to rearrange
Suspicious Startup Folder LNK Persistence Creation via File System (via file_event)
Suspicious XWorm Persistence Run Key Pointing to Batch Loader via ScreenConnect Lure (via registry_set)
Suspicious Run Key Persistence Named AppResolver (via registry_set)
Suspicious SystemBC Persistence via Run Key to ProgramData Script
Suspicious Interlock RAT Persistence via HKCU Run Key Registration to AppData Payload (via process_creation)
Suspicious SOCKS Proxy Persistence via SystemBC PowerShell Run Key
Suspicious Run Key Persistence Referencing PowerShell Script via registry_set
Malicious Startup Persistence via WindowsDefenderSync Shortcut (via file_event)
Malicious PXA Stealer Persistence via Windows Update Service Run Key (via registry_set)
Malicious WmRAT Persistence via vcswin Run Key (via registry_set)
Pivot detection · T1547.001 · 9 related

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