CVE-2021-36187 Denial of service in Fortinet FortiWeb

What is CVE-2021-36187?

CVE-2021-36187 is a medium-severity denial of service vulnerability in Fortinet Fortiweb, published on 2 Nov 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A uncontrolled resource consumption in Fortinet FortiWeb version 6.4.0, version 6.3.15 and below, 6.2.5 and below allows attacker to cause a denial of service for webserver daemon via crafted HTTP requests

Weakness: CWE-400

Which versions are affected by CVE-2021-36187?

It affects 1 product.

Products include Fortinet Fortiweb.

How do I fix CVE-2021-36187?

No fix has been published for CVE-2021-36187 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-2021-36187 being exploited?

There is no known exploitation of CVE-2021-36187 in the wild and no public exploit code.

Other vulnerabilities in Fortinet Fortiweb

• CVE-2025-25257 Fortinet FortiWeb SQL Injection Exploited Critical 9.6
• CVE-2025-64446 Fortinet FortiWeb Path Traversal Exploited Critical 9.4
• CVE-2025-58034 Fortinet FortiWeb OS Command Injection Exploited Medium 6.7
• CVE-2020-29015 SQL injection in Fortinet FortiWeb Critical 9.8
• CVE-2020-29016 Memory corruption in Fortinet FortiWeb Critical 9.8

All Fortinet Fortiweb vulnerabilities

Sources

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

Also known as GHSA-f52h-53cg-xm8m.