Suspicious Executable or Script Written to Windows Fonts Directory by FishMonger

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1574.001DLL
Persistence
- T1574.001DLL
Priv Esc
- T1574.001DLL
Defense Evasion
- T1574.001DLL
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects creation of batch, executable or DLL files inside the Windows Fonts directory, a hiding location used by the FishMonger group when staging SprySOCKS loader scripts such as klelam00007.bat. The Fonts folder normally holds only font resources, so script and binary drops there indicate masquerading and artifact concealment. Detecting this anomalous write path is important because it surfaces staged payloads placed in a trusted system location.

Reporting behind it

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Suspicious Executable or Script Written to Windows Fonts Directory by FishMonger

Pivot detection · T1574.001 · 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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