Suspicious JScript.NET Compiler Spawned by AutoIt for Process Hollowing

ATT&CK techniques

Priv Esc → Defense Evasion

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

What it detects

This rule detects jsc.exe being launched by AutoIt3.exe, a chain used by CastleLoader to create a suspended JScript.NET compiler process that is later hollowed with an injected PE. A jsc.exe process spawned from AutoIt3 is highly unusual in benign environments.

Reporting behind it

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Suspicious AppLaunch.exe Execution as Process Hollowing Target

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Suspicious JScript.NET Compiler Spawned by AutoIt for Process Hollowing

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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