Suspicious Execution of cfmon.exe Masquerading as ctfmon via CharmingCypress

ATT&CK techniques

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

What it detects

This rule detects execution of cfmon.exe a masqueraded binary used by CharmingCypress to patch AMSI and ETW in memory. The name mimics the legitimate Windows ctfmon.exe to evade casual inspection. Disabling AMSI and ETW blinds endpoint defenses to subsequent malicious activity.

Reporting behind it

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Suspicious Execution of cfmon.exe Masquerading as ctfmon via CharmingCypress

Pivot detection · T1685 · 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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