Suspicious Double Extension docx Executable Execution (via process_creation)

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1204.002Malicious File
Persistence
Priv Esc
Defense Evasion
- T1036.007Double File Extension
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects execution of a binary whose filename carries a double extension combining a document extension and padded spaces before .exe, the lure delivery technique used by Kimsuky against Japanese organizations. The masqueraded filename is designed to trick users into launching an executable they believe is a Word document.

Reporting behind it

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Suspicious Double Extension docx Executable Execution (via process_creation)

Pivot detection · T1204.002 · 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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