Suspicious mscorsvw Side-Loading mscorsvc DLL from Assembly Path

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 mscorsvw.exe loading mscorsvc.dll from the Windows assembly directory. The covert C2 backdoor plants a malicious mscorsvc.dll in this path so the trusted .NET optimizer side-loads it. This DLL hijack lets the attacker execute code under a signed Microsoft process.

Reporting behind it

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Suspicious mscorsvw Side-Loading mscorsvc DLL from Assembly Path

Pivot detection · T1574.001 · 9 related

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