Detectionmediumtest

File Decryption Using Gpg4win

Detects usage of Gpg4win to decrypt files

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Launch
Nasreddine Bencherchali (Nextron Systems)Created Wed Aug 09037dcd71-33a8-4392-bb01-293c94663e5awindows
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 Logic2 selectors
detection:
    selection_metadata:
        - Image|endswith:
              - '\gpg.exe'
              - '\gpg2.exe'
        - Description: 'GnuPG’s OpenPGP tool'
    selection_cli:
        CommandLine|contains|all:
            - ' -d '
            - 'passphrase'
    condition: all of selection_*
False Positives
Unknown

False positive likelihood has not been assessed. Additional context may be needed during triage.

MITRE ATT&CK
Rule Metadata
Rule ID
037dcd71-33a8-4392-bb01-293c94663e5a
Status
test
Level
medium
Type
Detection
Created
Wed Aug 09
Path
rules/windows/process_creation/proc_creation_win_gpg4win_decryption.yml
Raw Tags
attack.execution
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