FortiGate - User Group Modified

Title: FortiGate - User Group Modified
Status: experimental
Description:Detects the modification of a user group on a Fortinet FortiGate Firewall. The group could be used to grant VPN access to a network.
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/328136827/config-user-group
  -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
modified:None
Tags:

• -'attack.persistence'
• -'attack.privilege-escalation'

Logsource:

• product: fortigate
• service: event

Detection:
  selection:
    action: 'Edit'
    cfgpath: 'user.group'
  condition:selection
Falsepositives:
  -A group can be modified for legitimate purposes.
Level: medium