Suspicious Flax Typhoon System Utility Masquerade Outside System32 via Renamed VPN Client (via process_creation)

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 processes named conhost.exe or dllhost.exe executing from a directory other than the Windows system folders. Flax Typhoon renamed the SoftEther VPN client to these trusted binary names to blend in while tunneling traffic over TCP 443 for covert remote access.

Reporting behind it

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Suspicious Flax Typhoon System Utility Masquerade Outside System32 via Renamed VPN Client (via process_creation)

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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