sigmamediumHunting

FortiGate - New Local User Created

Detects the creation of a new local user on a Fortinet FortiGate Firewall. The new local user could be used for VPN connections.

MITRE ATT&CK

T1136.001

persistence

Detection Query

selection:
  action: Add
  cfgpath: user.local
condition: selection

Author

Marco Pedrinazzi @pedrinazziM (InTheCyber)

Created

2025-11-01

Data Sources

fortigateevent

Platforms

fortigate

References

Tags

attack.persistenceattack.t1136.001

Raw Content

title: FortiGate - New Local User Created
id: ddbbe845-1d74-43a8-8231-2156d180234d
status: experimental
description: |
    Detects the creation of a new local user on a Fortinet FortiGate Firewall.
    The new local user could be used for VPN connections.
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/109120963/config-user-local
    - 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: 'user.local'
    condition: selection
falsepositives:
    - A local user can be created for legitimate purposes. Investigate the user details to determine if it is authorized.
level: medium