SigmaHQ/rules/windows/process_creation/win_renamed_binary.yml

title: Renamed Binary
status: experimental
description: Detects the execution of a renamed binary often used by attackers or malware leveraging new Sysmon OriginalFileName datapoint.
author: Matthew Green - @mgreen27 
date: 2019/06/15
references:
    - https://attack.mitre.org/techniques/T1036/
    - https://mgreen27.github.io/posts/2019/05/12/BinaryRename.html
    - https://mgreen27.github.io/posts/2019/05/29/BinaryRename2.html
tags:
    - attack.t1036
    - attack.defense_evasion
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        OriginalFileName:
            - "cmd.exe"
            - "powershell.exe"
            - "powershell_ise.exe"
            - "psexec.exe"
            - "psexec.c"  # old versions of psexec (2016 seen)
            - "cscript.exe"
            - "wscript.exe"
            - "mshta.exe"
            - "regsvr32.exe"
            - "wmic.exe"
            - "certutil.exe"
            - "rundll32.exe"
            - "cmstp.exe"
            - "msiexec.exe"
            - "7z.exe"
            - "winrar.exe"
    filter:
        Image:
            - '*\cmd.exe'
            - '*\powershell.exe'
            - '*\powershell_ise.exe'
            - '*\psexec.exe'
            - '*\psexec64.exe'
            - '*\cscript.exe'
            - '*\wscript.exe'
            - '*\mshta.exe'
            - '*\regsvr32.exe'
            - '*\wmic.exe'
            - '*\certutil.exe'
            - '*\rundll32.exe'
            - '*\cmstp.exe'
            - '*\msiexec.exe'
            - '*\7z.exe'
            - '*\winrar.exe'
    condition: selection and not filter
falsepositives:
    - Custom applications use renamed binaries adding slight change to binary name. Typically this is easy to spot and add to whitelist
level: medium