SynkLoader Python Stager Execution from AppData via pythonw (via process_creation)

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 the SynkLoader Python stager launched by pythonw.exe from a randomly named AppData subdirectory using the fl\ang\ss.py path layout observed after a Microsoft Teams phishing lure. Adversaries run the loader silently to decrypt and inject follow-on modules while evading command-line script inspection, making early detection critical for stopping module deployment before credential theft.

Reporting behind it

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SynkLoader Python Stager Execution from AppData via pythonw (via process_creation)

Pivot detection · T1059.006 · 9 related

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