Malicious Coyote Persistence via UserInitMprLogonScript Environment Value (via registry_set)

ATT&CK techniques

Persistence → Priv Esc

Recon
Resource Dev
Initial Access
Execution
Persistence
- T1037Boot or Logon Initialization Scripts
- T1547.001Registry Run Keys / Startup Folder
Priv Esc
- T1037Boot or Logon Initialization Scripts
- T1547.001Registry Run Keys / Startup Folder
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects a write to the HKCU\Environment\UserInitMprLogonScript registry value pointing at an executable. The Coyote banking trojan sets this logon-script value to run obs-browser-page.exe at each user logon for persistence, so modification of this rarely-used key indicates a logon-script persistence mechanism being installed.

Reporting behind it

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Malicious Coyote Persistence via UserInitMprLogonScript Environment Value (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.

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