Suspicious Execution of Portable Gpg.EXE (via process_creation)

title: Suspicious Execution of Portable Gpg.EXE (via process_creation)
id: 3f6139ae-08b3-5e44-96d2-5872a6233481
status: stable
description: This rule detects the execution of "gpg.exe" from uncommon location. Frequently used by ransomware and loaders to decrypt/encrypt data.
references:
    - https://attack.mitre.org/techniques/T1486/
    - https://www.trendmicro.com/vinfo/vn/threat-encyclopedia/malware/ransom.bat.zarlock.a
    - https://securelist.com/locked-out/68960/
    - https://github.com/redcanaryco/atomic-red-team/blob/c4097dc7ed14d7f7d08c89d148c4307097e8c294/atomics/T1486/T1486.md
author: Huntrule Team
date: 2026-01-27
tags:
    - attack.impact
    - attack.t1486
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        - Image|endswith:
              - '\gpg.exe'
              - '\gpg2.exe'
        - OriginalFileName: 'gpg.exe'
        - Description: 'GnuPG’s OpenPGP tool'
    filter_main_legit_location:
        Image|contains:
            - ':\Program Files (x86)\GNU\GnuPG\bin\'
            - ':\Program Files (x86)\GnuPG VS-Desktop\'
            - ':\Program Files (x86)\GnuPG\bin\'
            - ':\Program Files (x86)\Gpg4win\bin\'
    filter_hr:
        Image|contains:
            - :\Program Files\Git\usr\bin\
            - :\Program Files (x86)\Git\usr\bin\
    condition: (selection and not 1 of filter_main_*) and not filter_hr
falsepositives:
    - Unknown
level: medium