Detectionmediumtest

Suspicious Windows Defender Folder Exclusion Added Via Reg.EXE

Detects the usage of "reg.exe" to add Defender folder exclusions. Qbot has been seen using this technique to add exclusions for folders within AppData and ProgramData.

Convert In Phoenix Studio

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

Launch

François HubautCreated Sun Feb 13Updated Sat Feb 0448917adc-a28e-4f5d-b729-11e75da8941fwindows

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:
        Image|endswith: '\reg.exe'
        CommandLine|contains:
            - 'SOFTWARE\Microsoft\Windows Defender\Exclusions\Paths'
            - 'SOFTWARE\Microsoft\Microsoft Antimalware\Exclusions\Paths'
        CommandLine|contains|all:
            - 'ADD '
            - '/t '
            - 'REG_DWORD '
            - '/v '
            - '/d '
            - '0'
    condition: selection