sigmamediumHunting

FortiGate - New VPN SSL Web Portal Added

Detects the addition of a VPN SSL Web Portal on a Fortinet FortiGate Firewall. This behavior was observed in pair with modification of VPN SSL settings.

MITRE ATT&CK

T1133

persistenceinitial-access

Detection Query

selection:
  action: Add
  cfgpath: vpn.ssl.web.portal
condition: selection

Author

Marco Pedrinazzi @pedrinazziM (InTheCyber)

Created

2025-11-01

Data Sources

fortigateevent

Platforms

fortigate

References

Tags

attack.persistenceattack.initial-accessattack.t1133

Raw Content

title: FortiGate - New VPN SSL Web Portal Added
id: 2bfb6216-0c31-4d20-8501-2629b29a3fa2
status: experimental
description: |
    Detects the addition of a VPN SSL Web Portal on a Fortinet FortiGate Firewall.
    This behavior was observed in pair with modification of VPN SSL settings.
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/113121765/config-vpn-ssl-web-portal
    - 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.initial-access
    - attack.t1133
logsource:
    product: fortigate
    service: event
detection:
    selection:
        action: 'Add'
        cfgpath: 'vpn.ssl.web.portal'
    condition: selection
falsepositives:
    - A VPN SSL Web Portal can be added for legitimate purposes.
level: medium