Suspicious Logon Script Persistence via UserInitMprLogonScript
- Product
- windows
- Category
- registry_set
- Author
- HuntRule
- Published
- 2026-10-21
- Updated
- 2026-10-21
ATT&CK techniques
Persistence → Priv EscRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule detects modification of the HKCU Environment UserInitMprLogonScript value, which registers a script that runs at each user logon. The Blitz malware abuses this rarely-used key for persistence. Because few legitimate applications set this value, changes are a high-confidence persistence indicator.
Reporting behind it
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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Also included
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