Malicious rundll32 vbscript mshtml RunHTMLApplication Execution

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1059.005Visual Basic
Persistence
Priv Esc
Defense Evasion
- T1218.011Rundll32
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects rundll32.exe invoking the vbscript protocol handler with mshtml RunHTMLApplication to execute inline script, a living-off-the-land technique used by the Sibot malware to run RegRead logic and retrieve its second stage. This LOLBin invocation has no legitimate use and bypasses application controls. Its presence indicates in-memory script execution and defense evasion.

Reporting behind it

Related detections9 linkedT1059.005 — drag to rearrange

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Malicious rundll32 vbscript mshtml RunHTMLApplication Execution

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.

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