Emerging Threathightest

Kapeka Backdoor Execution Via RunDLL32.EXE

Detects Kapeka backdoor process execution pattern, where the dropper launch the backdoor binary by calling rundll32 and passing the backdoor's first export ordinal (#1) with a "-d" argument.

Convert In Phoenix Studio

Open this Sigma rule in the converter with the YAML preloaded and ready for backend selection.

Launch

Swachchhanda Shrawan Poudel, Nasreddine Bencherchali (Nextron Systems)Created Wed Jul 03e98f741c-6a5b-4c83-bc2a-1f4e58d07b122024

Emerging Threat

Active Threat

Developed to detect an active or emerging threat. Prioritize investigation of any alerts and correlate with threat intelligence.

Log Source

WindowsProcess Creation

ProductWindows← raw: windows

CategoryProcess Creation← raw: process_creation

Events generated when a new process is spawned on the system. Covers command-line arguments, parent/child relationships, and process metadata.

Detection Logic

detection:
    selection_img:
        - Image|endswith: '\rundll32.exe'
        - OriginalFileName: 'RUNDLL32.EXE'
    selection_backdoor_path:
        CommandLine|contains:
            - ':\ProgramData'
            - '\AppData\Local'
    selection_backdoor_exec_1:
        CommandLine|contains|all:
            - '.wll'
            - '#1'
            - ' -d'
    selection_backdoor_exec_2:
        # This account for the in the wild variant
        CommandLine|contains: '.wll'
        CommandLine|endswith: '#1'
    condition: selection_img and selection_backdoor_path and 1 of selection_backdoor_exec_*