Suspicious PowerShell Invoking Remote HTA via Environment Variable Masquerading (via process_creation)

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1059.001PowerShell
Persistence
Priv Esc
Defense Evasion
- T1027Obfuscated Files or Information
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects PowerShell command lines that reference an environment-variable path together with a remote HTA URL. The CMSTP LNK loader uses this masquerading technique to launch mshta against attacker infrastructure.

Reporting behind it

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Suspicious PowerShell Invoking Remote HTA via Environment Variable Masquerading (via process_creation)

Pivot detection · T1027 · 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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