Character — Sigma Rule. Detects the creation of a user with the "content="Sigma rule cfeed607-6aa4-4bbd-9627-b637deb723c8. New or Renamed User Account with '$' Character — Sigma Rule. Detects the creation of a user with the "$" character. This can be used by attackers to hide a user or trick detection systems that lack the parsing mechanisms. "quot;…"> Character — Sigma Rule" or Renamed User Account with '> Character — Sigma Rule"> Character — Sigma Rule. Detects the creation of a user with the "content="Sigma rule cfeed607-6aa4-4bbd-9627-b637deb723c8. New or Renamed User Account with '$' Character — Sigma Rule. Detects the creation of a user with the "$" character. This can be used by attackers to hide a user or trick detection systems that lack the parsing mechanisms. "quot;…"> Character — Sigma Rule" or Renamed User Account with '> Character — Sigma Rule"> Character — Sigma Rule. Detects the creation of a user with the "content="Sigma rule cfeed607-6aa4-4bbd-9627-b637deb723c8. New or Renamed User Account with '$' Character — Sigma Rule. Detects the creation of a user with the "$" character. This can be used by attackers to hide a user or trick detection systems that lack the parsing mechanisms. "quot;…">
1200kmSECURITY RESEARCH

1200KM / sigma-rule

New or Renamed User Account with '$' Character — Sigma Rule

Sigma rule cfeed607-6aa4-4bbd-9627-b637deb723c8. New or Renamed User Account with '$' Character — Sigma Rule. Detects the creation of a user with the "$" character. This can be used by attackers to hide a user or trick detection systems that lack the parsing mechanisms.

Rule metadata and linked tags

testmediumwindowssecurityattack.stealthattack.t1036

Author: Ilyas Ochkov, oscd.community. Source status: test; severity: medium. Source dates: 2019-10-25 / 2024-01-16.

{
  "product": "windows",
  "service": "security"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: b6c0b0480d29657c914dd954a6e581cb2c9bad347231f8461a21dca50e89522b

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 or Renamed User Account with '$' Character
id: cfeed607-6aa4-4bbd-9627-b637deb723c8
status: test
description: |
    Detects the creation of a user with the "$" character. This can be used by attackers to hide a user or trick detection systems that lack the parsing mechanisms.
references:
    - https://twitter.com/SBousseaden/status/1387743867663958021
author: Ilyas Ochkov, oscd.community
date: 2019-10-25
modified: 2024-01-16
tags:
    - attack.stealth
    - attack.t1036
logsource:
    product: windows
    service: security
detection:
    selection_create:
        EventID: 4720 # create user
        SamAccountName|contains: '$'
    selection_rename:
        EventID: 4781 # rename user
        NewTargetUserName|contains: '$'
    filter_main_homegroup:
        EventID: 4720
        TargetUserName: 'HomeGroupUser$'
    condition: 1 of selection_* and not 1 of filter_main_*
falsepositives:
    - Unknown
level: medium

Original YAML and metadata in JSON

False positives

  • Unknown

Source references

Connected ecosystem references

Exact source-tagged techniques

Telemetry review

Read the original logsource above, then inspect the linked detection workspaces for technique-level sensor context. No per-rule telemetry equivalence is inferred.

Pinned research references. No browser attack runner, live simulation result or validated detector is asserted. Source mappings and validation limits are preserved. ATT&CK / Atomic provenance · Detection provenance.