Threat Huntmediumstable

DLL Call by Ordinal Via Rundll32.EXE

Detects calls of DLLs exports by ordinal numbers via rundll32.dll.

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Launch
Florian Roth (Nextron Systems)Created Tue Oct 22Updated Tue Jul 16e79a9e79-eb72-4e78-a628-0e7e8f59e89cwindows
Hunting Hypothesis
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 Logic4 selectors
detection:
    selection_img:
        - Image|endswith: '\rundll32.exe'
        - OriginalFileName: 'RUNDLL32.EXE'
    selection_cli:
        CommandLine|contains:
            - ',#'
            - ', #'
            - '.dll #'  # Sysmon removes , in its log
            - '.ocx #'  # HermeticWizard
    filter_optional_edge:
        CommandLine|contains|all:
            - 'EDGEHTML.dll'
            - '#141'
    filter_optional_vsbuild_dll:
        ParentImage|contains:
            - '\Msbuild\Current\Bin\'
            - '\VC\Tools\MSVC\'
            - '\Tracker.exe'
        CommandLine|contains:
            - '\FileTracker32.dll,#1'
            - '\FileTracker32.dll",#1'
            - '\FileTracker64.dll,#1'
            - '\FileTracker64.dll",#1'
    condition: all of selection_* and not 1 of filter_optional_*
False Positives

False positives depend on scripts and administrative tools used in the monitored environment.

Windows control panel elements have been identified as source (mmc).

MITRE ATT&CK

Sub-techniques

Other

detection.threat-hunting
Rule Metadata
Rule ID
e79a9e79-eb72-4e78-a628-0e7e8f59e89c
Status
stable
Level
medium
Type
Threat Hunt
Created
Tue Oct 22
Modified
Tue Jul 16
Path
rules-threat-hunting/windows/process_creation/proc_creation_win_rundll32_by_ordinal.yml
Raw Tags
attack.defense-evasionattack.t1218.011detection.threat-hunting
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