Suspicious RegAsm Process Hollowing for DarkCloud Stealer

ATT&CK techniques

Priv Esc → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
- T1055.012Process Hollowing
Defense Evasion
- T1055.012Process Hollowing
- T1218System Binary Proxy Execution
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects RegAsm.exe launching outside of normal .NET build or install workflows. The DarkCloud stealer infection chain injects its payload into a hollowed RegAsm.exe process to execute under a trusted Microsoft binary. RegAsm running without a legitimate .NET tooling parent is a strong process hollowing indicator.

Reporting behind it

Related detections9 linkedT1055.012 — drag to rearrange

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Suspicious JScript.NET Compiler Spawned by AutoIt for Process Hollowing

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PureHVNC Process Hollowing into RegAsm Spawned by PowerShell (via process_creation)

Malicious aspnet_compiler.exe Injection Host Spawned by PowerShell via process_creation

Suspicious DotNet Utility Spawned by Script Host for Hollowing (via process_creation)

Malicious regsvcs LOLBin Loading Ransomware DLL from UNC Path

Suspicious RegSvcs Reflective .NET Load from Fake Update Chain

Suspicious RegAsm Process Hollowing for DarkCloud Stealer

Pivot detection · T1055.012 · 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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