Suspicious rundll32 or mshta Proxy Execution of VBScript

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 rundll32.exe or mshta.exe invoked with a vbscript protocol handler to proxy execution of Visual Basic script, the living-off-the-land method used to run VBScript that is stored in the registry or delivered inline. This technique bypasses application control by abusing a signed system binary as the script host. Such invocations have no legitimate administrative purpose.

Reporting behind it

Related detections9 linkedT1059.005 — drag to rearrange

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 Office Application Spawning Script Interpreter

Suspicious mshta Execution of Remote or Inline Payload (via process_creation)

Malicious rundll32 vbscript mshtml RunHTMLApplication Execution

Suspicious Script Host Spawned by cmd for DarkGate Execution

Suspicious GammaLoad VBScript Execution via wscript.exe (via process_creation)

Suspicious mshta Execution Proxied Through pcalua LOLBIN

Suspicious rundll32 or mshta Proxy Execution of VBScript

Pivot detection · T1059.005 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

Full detection rule

Unlock this rule to view and copy it

The detection logic is included with a plan. Everything else — context, mappings and implementation details — stays free on this page.

Sign in for 3 free unlocks

Signing in gives you 3 unlocks to spend on any rule in the library. No card, and they do not expire.

Also included

Unlocked rules convert on this page — to Splunk SPL or Splunk — Raw Index SPL or Microsoft Sentinel KQL or Microsoft Sentinel ASIM ASIM KQL or Microsoft Defender XDR KQL or Elastic Security KQL or Elastic Security Lucene or Elastic Security ES|QL or CrowdStrike Falcon CQL or SentinelOne PowerQuery or Palo Alto Cortex XDR XQL or Carbon Black Cloud Platform Search or Carbon Black EDR Process Search or Google Security Operations UDM Search or IBM QRadar AQL or Sumo Logic Cloud SIEM Rules expression or Rapid7 InsightIDR LEQL or Graylog Search or OpenSearch Lucene or OpenSearch PPL PPL or Grafana Loki LogQL or SQLite SQL or Zircolite SQLite — with the log-source profile the engine picked, the field map it used, and everything it could not express. Converting a rule you have unlocked costs no further credit.

See it run on a free rule →Convert your own rule →