Malicious Remote HTA Download and Execution via mshta by UAC-0050 (via process_creation)

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1059.001PowerShell
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 a remote HTA file over HTTP or HTTPS, the initial download stage of the UAC-0050 RemcosRAT infection chain. The actor uses a LNK to launch mshta against a remote hta which unpacks a VBS and PowerShell loader. Detecting proxy-aware remote HTA execution catches the intrusion at its delivery stage.

Reporting behind it

Related detections9 linkedT1059.001 — drag to rearrange

Suspicious PowerShell Spawning mshta for Malware Execution (via process_creation)

Malicious Metasploit Stager Delivery via mshta Remote HTA (via process_creation)

Suspicious PowerShell Spawned by mshta.exe in FakeSG Chain (via process_creation)

Suspicious Hidden PowerShell Spawned by MSHTA for Boot Persistence (via process_creation)

Malicious HTA Payload Download and Execution via PowerShell One-Liner (via process_creation)

Suspicious PowerShell Loader Spawned by mshta via UNC5142 ClickFix

Suspicious Script Interpreter Spawned by mshta

Malicious mshta Spawning PowerShell Loader via ClickFix

Malicious Forfiles Proxy Execution Launching PowerShell and MSHTA in PEAKLIGHT Chain (via process_creation)

Malicious Remote HTA Download and Execution via mshta by UAC-0050 (via process_creation)

Pivot detection · T1059.001 · 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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