Detectionhightest

Potential Mpclient.DLL Sideloading Via Defender Binaries

Detects potential sideloading of "mpclient.dll" by Windows Defender processes ("MpCmdRun" and "NisSrv") from their non-default directory.

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Bhabesh RajCreated Mon Aug 01Updated Fri Aug 047002aa10-b8d4-47ae-b5ba-51ab07e228b9windows
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 Logic2 selectors
detection:
    selection:
        Image|endswith:
            - '\MpCmdRun.exe'
            - '\NisSrv.exe'
    filter_main_known_locations:
        Image|startswith:
            - 'C:\Program Files (x86)\Windows Defender\'
            - 'C:\Program Files\Microsoft Security Client\'
            - 'C:\Program Files\Windows Defender\'
            - 'C:\ProgramData\Microsoft\Windows Defender\Platform\'
            - 'C:\Windows\WinSxS\'
    condition: selection and not 1 of filter_main_*
False Positives
Unlikely

False positives are unlikely for most environments. High confidence detection.

Rule Metadata
Rule ID
7002aa10-b8d4-47ae-b5ba-51ab07e228b9
Status
test
Level
high
Type
Detection
Created
Mon Aug 01
Modified
Fri Aug 04
Path
rules/windows/process_creation/proc_creation_win_mpcmdrun_dll_sideload_defender.yml
Raw Tags
attack.privilege-escalationattack.persistenceattack.defense-evasionattack.t1574.001
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