Malicious KrustyLoader Relocation and Self Delete Artifacts

ATT&CK techniques

Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1027Obfuscated Files or Information
- T1070.004File Deletion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects execution of the relocated or self deleting copies that the KrustyLoader Windows variant creates in the user temp directory as described by WithSecure where the loader renamed itself with relocated and selfdelete markers to frustrate analysis and remove its on disk trace. These fixed filename markers are highly specific loader artifacts that indicate an active KrustyLoader stager and indicator removal.

Reporting behind it

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Malicious KrustyLoader Relocation and Self Delete Artifacts

Pivot detection · T1027 · 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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