Malicious Fseventsd Masquerade in Users Shared Directory via File Event

ATT&CK techniques

Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1036.005Match Legitimate Resource Name or Location
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects creation of a hidden fseventsd named file inside the Users Shared directory which the macOS pirate ship campaign drops to masquerade its payload as a legitimate filesystem events daemon artifact. The genuine fseventsd store does not live in Users Shared so this file placement is a defense evasion masquerade.

Reporting behind it

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Malicious Fseventsd Masquerade in Users Shared Directory via File Event

Pivot detection · T1036.005 · 9 related

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