Sysmon Discovery Via Default Driver Altitude Using Findstr.EXE — Sigma Rule

Rule metadata and linked tags

Author: frack113. Source status: test; severity: high. Source dates: 2021-12-16 / 2023-11-14.

{
  "category": "process_creation",
  "product": "windows"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: f57554d6754814b697859e4b8bb14989896b9c4e83962e55b032da6bd6edf0f9

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Sysmon Discovery Via Default Driver Altitude Using Findstr.EXE
id: 37db85d1-b089-490a-a59a-c7b6f984f480
status: test
description: Detects usage of "findstr" with the argument "385201". Which could indicate potential discovery of an installed Sysinternals Sysmon service using the default driver altitude (even if the name is changed).
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1518.001/T1518.001.md#atomic-test-5---security-software-discovery---sysmon-service
author: frack113
date: 2021-12-16
modified: 2023-11-14
tags:
    - attack.discovery
    - attack.t1518.001
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith:
              - '\find.exe'
              - '\findstr.exe'
        - OriginalFileName:
              - 'FIND.EXE'
              - 'FINDSTR.EXE'
    selection_cli:
        CommandLine|contains: ' 385201' # Sysmon driver default altitude
    condition: all of selection_*
falsepositives:
    - Unknown
level: high

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1518.001/T1518.001.md#atomic-test-5---security-software-discovery---sysmon-service