Malicious Rundll32 RunHTMLApplication Remote Execution

ATT&CK techniques

Defense Evasion

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

What it detects

This rule detects rundll32.exe invoking mshtml RunHTMLApplication with a remote http URL and path traversal to proxy execution of a remote HTA. In the WithSecure Initial Access Lab 2 the Koadic framework stages via rundll32 calling mshtml,RunHTMLApplication against an attacker web server. Attackers use this signed binary technique to run remote scriptlets and bypass application controls.

Reporting behind it

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Malicious Rundll32 RunHTMLApplication Remote Execution

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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