Detectionmediumtest

Potentially Suspicious Execution Of Regasm/Regsvcs From Uncommon Location

Detects potentially suspicious execution of the Regasm/Regsvcs utilities from a potentially suspicious location

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Nasreddine Bencherchali (Nextron Systems)Created Thu Aug 25Updated Mon Feb 13cc368ed0-2411-45dc-a222-510ace303cb2windows

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:
              - '\Regsvcs.exe'
              - '\Regasm.exe'
        - OriginalFileName:
              - 'RegSvcs.exe'
              - 'RegAsm.exe'
    selection_dir:
        CommandLine|contains:
            # Note: Add more potentially suspicious directories
            - '\AppData\Local\Temp\'
            - '\Microsoft\Windows\Start Menu\Programs\Startup\'
            - '\PerfLogs\'
            - '\Users\Public\'
            - '\Windows\Temp\'
            # - '\Desktop\'
            # - '\Downloads\'
    condition: all of selection_*