FORTIOS · CVE-2026-126253 · Infrastructure
FIX → 8.0.2 · 7.6.8 · 7.4.13 · 7.2.14 ✓ verified
A flaw in Fortinet FortiOS authentication lets an unauthenticated attacker broadcast LSA (OSPF link-state) messages using a specially crafted request. The sources give a CVSS score of 9.3 but do not describe further consequences.
first public Nov 11, 2026 · 2 sources
Could this affect your app?
Free first check from your website. Connect your repo for the full answer.
Teams running FortiGate firewalls on FortiOS 7.0 to 8.0.1 in the listed ranges. The flaw is in the OSPF routing daemon and the vendor's vector is adjacent-network, so look first at firewalls that run OSPF toward untrusted or shared segments. Fortinet does not say OSPF must be enabled; sites without OSPF may be lower risk but should still upgrade. FortiSASE 26.3.1 needs no action.
Not affected if fortisase-24.4-or-earlier, fortisase-26.3.2-or-later
Who cares adjacent-network, firewall, fortinet, fortios, fortisase, ospf, routing
get system status on each FortiGate (or see Dashboard) and compare the version: affected are , , , , A authentication bypass by primary weakness vulnerability in Fortinet FortiOS 8.0.0 through 8.0.1, FortiOS 7.6.0 through 7.6.7, FortiOS 7.4.0 through 7.4.12, FortiOS 7.2.0 through 7.2.13 may allow an unauthenticated attacker to broadcast LSA via specially crafted request
This page as .md · .json · CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:H
NVD data is provided by NIST and is public domain. Posts quoted belong to their authors.
Check it with your coding agent
It reads this page and tells you if your code is affected.
Are you affected?
Ask from here. InfraStack checks the affected versions against your stack and answers in your inbox.
InfraStack checks the affected versions against your stack and answers in Slack, with the evidence and the fix.
8.0.0-8.0.17.6.0-7.6.77.4.0-7.4.127.2.0-7.2.137.0.1-7.0.19show router ospf) and which interfaces carry itUpgrade to 8.0.2 · 7.6.8 · 7.4.13 · 7.2.14
8.0.2, 7.6.8, 7.4.13 or 7.2.14 (or later)7.0.1-7.0.19): migrate to a fixed release26.3.1 already remediated by Fortinet in 26.3.2; FortiSASE 25.x-26.2 migrate