Detection rules › Sigma

FortiGate - New Administrator Account Created

Status
experimental
Severity
medium
Log source
product fortigate, service event
Author
Marco Pedrinazzi (@pedrinazziM) (InTheCyber)
Source
github.com/SigmaHQ/sigma

Detects the creation of an administrator account on a Fortinet FortiGate Firewall.

Known false positives

  • An administrator account can be created for legitimate purposes. Investigate the account details to determine if it is authorized.

MITRE ATT&CK coverage

TacticTechniques
Persistence

Rule body

title: FortiGate - New Administrator Account Created
id: cd0a4943-0edd-42cf-b50c-06f77a10d4c1
status: experimental
description: Detects the creation of an administrator account on a Fortinet FortiGate Firewall.
references:
    - https://www.fortiguard.com/psirt/FG-IR-24-535
    - https://docs.fortinet.com/document/fortigate/7.6.4/fortios-log-message-reference/398/event
    - https://docs.fortinet.com/document/fortigate/7.6.4/cli-reference/390485493/config-system-admin
    - https://docs.fortinet.com/document/fortigate/7.6.4/fortios-log-message-reference/44547/44547-logid-event-config-objattr
author: Marco Pedrinazzi (@pedrinazziM) (InTheCyber)
date: 2025-11-01
tags:
    - attack.persistence
    - attack.t1136.001
logsource:
    product: fortigate
    service: event
detection:
    selection:
        action: 'Add'
        cfgpath: 'system.admin'
    condition: selection
falsepositives:
    - An administrator account can be created for legitimate purposes. Investigate the account details to determine if it is authorized.
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    action: 'Add'
    cfgpath: 'system.admin'

Indicators

These rows show field, operator, and value matches.