Detectionmediumtest

Msiexec Quiet Installation

Adversaries may abuse msiexec.exe to proxy execution of malicious payloads. Msiexec.exe is the command-line utility for the Windows Installer and is thus commonly associated with executing installation packages (.msi)

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Launch

François HubautCreated Sun Jan 16Updated Sun Dec 0179a87aa6-e4bd-42fc-a5bb-5e6fbdcd62f5windows

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: '\msiexec.exe'
        - OriginalFileName: 'msiexec.exe'
    selection_cli:
        # Note that there is no space before and after the arguments because it's possible to write a commandline as such
        # Example: msiexec -q/i [MSI Package]
        CommandLine|contains|windash:
            - '-i'
            - '-package'
            - '-a'
            - '-j'
    selection_quiet:
        CommandLine|contains|windash: '-q'
    filter_user_temp:
        # The %temp% is a very common location for installers
        ParentImage|startswith: 'C:\Users\'
        ParentImage|contains: '\AppData\Local\Temp\'
    filter_system_temp:
        ParentImage|startswith: 'C:\Windows\Temp\'
    filter_ccm:
        ParentImage: 'C:\Windows\CCM\Ccm32BitLauncher.exe'
        IntegrityLevel:
            - 'System'
            - 'S-1-16-16384'
    condition: all of selection_* and not 1 of filter_*