TinyLoader Persistence via txtfile Shell Open Command Hijack (via registry_set)
- Product
- windows
- Category
- registry_set
- Author
- HuntRule
- Published
- 2026-07-25
- Updated
- 2026-08-28
ATT&CK techniques
Persistence → Priv EscRecon
Resource Dev
Initial Access
Execution
Persistence
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule detects modification of the txtfile shell open command handler so that opening any text file first launches an attacker binary, the file-association hijack TinyLoader uses for persistence. Adversaries leverage this handler so the loader runs whenever a user opens a .txt file, then still opens the file to avoid suspicion.
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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