Suspicious rundll32 Execution of IconCache Masquerading DLL

ATT&CK techniques

Defense Evasion

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

What it detects

This rule detects rundll32.exe executing a DLL located in the Explorer icon cache directory with an iconcache prefixed name. In Operation ForumTroll rundll32 was used as a proxy to load the payload DLL dropped to this path as reported by Kaspersky. Proxied execution of a masquerading DLL from a user profile cache directory is a strong signed binary proxy and defense evasion indicator.

Reporting behind it

Related detections9 linkedT1218.011 — drag to rearrange

Malicious LSASS Credential Dump via rundll32 and comsvcs MiniDump

Suspicious Rundll32 Execution Without Arguments

Malicious rundll32 Execution of BoomBox NativeCache DLL (via process_creation)

Malicious rundll32 vbscript mshtml RunHTMLApplication Execution

Malicious rundll32 WebDAV UNC Execution over HTTP

Suspicious rundll32 Execution of DLL from WebDAV Share (via process_creation)

Suspicious DLL Execution via rundll32 from PerfLogs Directory

Malicious DarkMe COM Object Execution via rundll32 CLSID

Suspicious rundll32 Control_RunDLL DLL Execution

Suspicious rundll32 Execution of IconCache Masquerading DLL

Pivot detection · T1218.011 · 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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