CVE-2026-71408 Denial of service in FortiOS

What is CVE-2026-71408?

CVE-2026-71408 is a medium-severity denial of service vulnerability in Fortinet Fortios, published on 12 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A allocation of resources without limits or throttling vulnerability in Fortinet FortiOS 7.6.0 through 7.6.6, FortiOS 7.4 all versions, FortiOS 7.2 all versions, FortiOS 7.0 all versions, FortiOS 6.4 all versions may allow an unauthenticated attacker to perform a slow HTTP DoS attack on the web interface via crafted HTTP requests.

Weakness: CWE-770

Which versions are affected by CVE-2026-71408?

It affects 1 product.

Products include Fortinet Fortios.

How do I fix CVE-2026-71408?

No fix has been published for CVE-2026-71408 yet. Limit exposure of the affected software until one is available.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2026-71408 being exploited?

There is no known exploitation of CVE-2026-71408 in the wild and no public exploit code.

Other vulnerabilities in Fortinet Fortios

• CVE-2024-23113 Fortinet Multiple Products Format String Exploited Critical 9.8
• CVE-2022-40684 Fortinet Multiple Products Authentication Bypass Exploited Critical 9.8
• CVE-2024-55591 Fortinet FortiOS and FortiProxy Authentication Bypass Exploited Critical 9.6
• CVE-2024-21762 Fortinet FortiOS Out-of-Bound Write Exploited Critical 9.6
• CVE-2022-42475 Fortinet FortiOS Heap-Based Buffer Overflow Exploited Critical 9.3

All Fortinet Fortios vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-xmwg-5p5q-jm2f.