Account Tampering - Suspicious Failed Logon Reasons — Sigma Rule

Rule metadata and linked tags

Author: Florian Roth (Nextron Systems). Source status: test; severity: medium. Source dates: 2017-02-19 / 2025-10-17.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: b5567dfa0e49d6119aa008844d3681228584b880f4249befa13b6e11a0dfaef4

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: Account Tampering - Suspicious Failed Logon Reasons
id: 9eb99343-d336-4020-a3cd-67f3819e68ee
status: test
description: This method uses uncommon error codes on failed logons to determine suspicious activity and tampering with accounts that have been disabled or somehow restricted.
references:
    - https://learn.microsoft.com/en-us/previous-versions/windows/it-pro/windows-10/security/threat-protection/auditing/event-4625
    - https://twitter.com/SBousseaden/status/1101431884540710913
author: Florian Roth (Nextron Systems)
date: 2017-02-19
modified: 2025-10-17
tags:
    - attack.persistence
    - attack.privilege-escalation
    - attack.initial-access
    - attack.stealth
    - attack.t1078
logsource:
    product: windows
    service: security
detection:
    selection_eid:
        EventID:
            - 4625
            - 4776
    selection_status:
        - Status:
              - '0xC0000072'  # User logon to account disabled by administrator
              - '0xC000006F'  # User logon outside authorized hours
              - '0xC0000070'  # User logon from unauthorized workstation
              - '0xC0000413'  # Logon Failure: The machine you are logging onto is protected by an authentication firewall. The specified account is not allowed to authenticate to the machine
              - '0xC000018C'  # The logon request failed because the trust relationship between the primary domain and the trusted domain failed
              - '0xC000015B'  # The user has not been granted the requested logon type (aka logon right) at this machine
        - SubStatus:
              - '0xC0000072'  # User logon to account disabled by administrator
              - '0xC000006F'  # User logon outside authorized hours
              - '0xC0000070'  # User logon from unauthorized workstation
              - '0xC0000413'  # Logon Failure: The machine you are logging onto is protected by an authentication firewall. The specified account is not allowed to authenticate to the machine
              - '0xC000018C'  # The logon request failed because the trust relationship between the primary domain and the trusted domain failed
              - '0xC000015B'  # The user has not been granted the requested logon type (aka logon right) at this machine
    filter:
        SubjectUserSid: 'S-1-0-0'
    condition: all of selection_* and not filter
falsepositives:
    - User using a disabled account
level: medium

Original YAML and metadata in JSON

False positives

• User using a disabled account

Source references

• https://learn.microsoft.com/en-us/previous-versions/windows/it-pro/windows-10/security/threat-protection/auditing/event-4625
• https://twitter.com/SBousseaden/status/1101431884540710913