Suspicious Double Extension Image Executable by Fighting Ursa

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1204.002Malicious File
Persistence
Priv Esc
Defense Evasion
- T1036Masquerading
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects execution of a file using a deceptive image double extension ending in jpg.exe, the disguise Fighting Ursa applies to a renamed calc.exe delivered in its car-for-sale phishing lure. The double extension tricks users into launching a program that appears to be a photo. Detecting this exposes user execution of the masqueraded first-stage binary.

Reporting behind it

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Suspicious Double Extension Image Executable by Fighting Ursa

Pivot detection · T1204.002 · 9 related

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