New User Created Via Net.EXE — Sigma Rule

Rule metadata and linked tags

Author: Endgame, JHasenbusch (adapted to Sigma for oscd.community). Source status: test; severity: medium. Source dates: 2018-10-30 / 2023-02-21.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 6e9c5d7ef5eaab2ecc8064d6f4176b22d9cd31676ad190ce554414212b7a4206

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: New User Created Via Net.EXE
id: cd219ff3-fa99-45d4-8380-a7d15116c6dc
related:
    - id: b9f0e6f5-09b4-4358-bae4-08408705bd5c
      type: similar
status: test
description: Identifies the creation of local users via the net.exe command.
references:
    - https://eqllib.readthedocs.io/en/latest/analytics/014c3f51-89c6-40f1-ac9c-5688f26090ab.html
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1136.001/T1136.001.md
author: Endgame, JHasenbusch (adapted to Sigma for oscd.community)
date: 2018-10-30
modified: 2023-02-21
tags:
    - attack.persistence
    - attack.t1136.001
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith:
              - '\net.exe'
              - '\net1.exe'
        - OriginalFileName:
              - 'net.exe'
              - 'net1.exe'
    selection_cli:
        CommandLine|contains|all:
            - 'user'
            - 'add'
    condition: all of selection_*
falsepositives:
    - Legitimate user creation.
    - Better use event IDs for user creation rather than command line rules.
level: medium

Original YAML and metadata in JSON

False positives

• Legitimate user creation.
• Better use event IDs for user creation rather than command line rules.

Source references

• https://eqllib.readthedocs.io/en/latest/analytics/014c3f51-89c6-40f1-ac9c-5688f26090ab.html
• https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1136.001/T1136.001.md