9.8Critical

Fortinet Fortiweb

CVE-2026-26035

An Improper Authentication vulnerability [CWE-287] vulnerability in Fortinet FortiWeb 8.0.0 through 8.0.2, FortiWeb 7.6.0 through 7.6.6, FortiWeb 7.4.0 through 7.4.11, FortiWeb 7.2.0 through 7.2.12, FortiWeb 7.0.0 through 7.0.12 may allow a remote unauthenticated attacker to login into the Fortiweb GUI/CLI with a random username and password

What this means for your business

  • It affects Fortinet Fortiweb. It matters if your company, or a supplier that handles your data, runs it.
  • An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
  • FIRST's prediction model gives it a 0.7% chance of attack attempts being seen in the next 30 days, ranking above 49% of all known flaws.

What to do

  1. 1Check whether your company or your suppliers run Fortinet Fortiweb, and which version. The affected versions are listed further down this page.
  2. 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.

Not sure if your company is exposed?

Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.

Scoring

CVSS
9.8 (v3.1)
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness
CWE-287
Assigned by
psirt@fortinet.com

Dates

Published
2026-08-12
Last modified
2026-09-08
Sources
NVD

Affected products

  • Fortinet Fortiweb7.2.0 - 7.2.13, 7.4.0 - 7.4.12, 7.6.0 - 7.6.7, 8.0.0 - 8.0.3

As listed in the NVD configuration data. Not a statement about your estate.

References