Malicious mshta Launching WScript VBScript Loader

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1059.005Visual Basic
Persistence
Priv Esc
Defense Evasion
- T1218.005Mshta
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects mshta.exe executing inline JavaScript that instantiates a WScript shell to run a VBScript payload, the initial execution chain used by Shuckworm to deploy GammaSteel from an infected removable drive.

Reporting behind it

Related detections9 linkedT1218.005 — drag to rearrange

Suspicious VBScript Code Stored in CurrentVersion Registry Value

Suspicious rundll32 or mshta Proxy Execution of VBScript

Suspicious MSHTA VBScript WScript Shell Execution

Windows: Alert on suspicious parent process spawning csc.exe

Windows Remote Thread Creation via CACTUSTORCH Using Script/Office/Rundll Host Images

Suspicious Kimsuky Remote HTA Payload Execution via mshta (via process_creation)

Suspicious wscript Execution Forcing VBScript Engine in Batch Mode

Suspicious mshta Execution of Inline JavaScript

Suspicious Command Interpreter Spawned by mshta (via process_creation)

Malicious mshta Launching WScript VBScript Loader

Pivot detection · T1218.005 · 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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