Malicious WARMCOOKIE Loader Execution via rundll32 RtlUpd via process_creation

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 the WARMCOOKIE backdoor DLL RtlUpd.dll with its Start export. The backdoor is dropped to the ProgramData RtlUpd directory and invoked through rundll32 for execution and persistence. This specific module and export combination is a high-confidence WARMCOOKIE indicator.

Reporting behind it

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Malicious WARMCOOKIE Loader Execution via rundll32 RtlUpd via process_creation

Pivot detection · T1218.011 · 9 related

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