Suspicious .NET LOLBin Execution via CasPol or RegAsm

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1127Trusted Developer Utilities Proxy Execution
Persistence
Priv Esc
Defense Evasion
- T1127Trusted Developer Utilities Proxy Execution
- T1218System Binary Proxy Execution
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects execution of the .NET Framework utilities CasPol.exe or RegAsm.exe spawned by a script interpreter. Batch and PowerShell loaders abuse these signed developer tools to load and run reflectively decrypted assemblies while bypassing application control.

Reporting behind it

Related detections9 linkedT1218 — drag to rearrange

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Suspicious .NET LOLBin Execution via CasPol or RegAsm

Pivot detection · T1218 · 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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