Malicious InvisibleFerret Python Loader Execution from Hidden .pyp Directory

ATT&CK techniques

Execution

Recon
Resource Dev
Initial Access
Execution
- T1059.006Python
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects a python.exe located in a hidden .pyp user directory executing the .npl payload, matching the InvisibleFerret stage of the North Korean job-hunter campaigns described by Unit 42. The actor stages a private Python runtime and payload under a dotted folder in the user profile which is an unusual pattern that reveals the second-stage backdoor.

Reporting behind it

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Malicious InvisibleFerret Python Loader Execution from Hidden .pyp Directory

Pivot detection · T1059.006 · 9 related

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