Suspicious WindowServer Binary Masquerade in Application Support (via file_event)

ATT&CK techniques

C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1090Proxy
Exfiltration
Impact

What it detects

This rule detects creation of a file named WindowServer under ~/Library/Application Support/ on macOS. The Trojan-Proxy drops its main executable using the name of a legitimate system service in this user directory to blend in, so a WindowServer binary written to Application Support rather than the OS location indicates masquerading malware.

Reporting behind it

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Suspicious WindowServer Binary Masquerade in Application Support (via file_event)

Pivot detection · T1090 · 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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