Suspicious DLL Sideloading via ProtonVPN Executable (via image_load)

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 the ProtonVPN executable loading a nethost.dll that has been abused for DLL sideloading by the STAC5143 threat cluster to establish command and control after Microsoft Teams social engineering. The sideloaded library beacons to attacker infrastructure while running under a trusted application name.

Reporting behind it

Related detections9 linkedT1574.001 — drag to rearrange

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Suspicious DLL Sideloading via ProtonVPN Executable (via image_load)

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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