Suspicious DLL Side-Loading from Non-Standard winsystem Directory

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 a module being loaded from the non-standard C:\winsystem directory used by the STARKVEIL chain to stage side-loaded DLLs alongside a legitimate signed executable. Attackers rely on this masquerading path to run malicious code under a trusted process while evading directory-based allowlists.

Reporting behind it

Related detections9 linkedT1574.001 — drag to rearrange

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Suspicious DLL Side-Loading from Non-Standard winsystem Directory

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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