CVE-2021-26090 Denial of service in Fortinet FortiMail

What is CVE-2021-26090?

CVE-2021-26090 is a medium-severity denial of service vulnerability in Fortinet FortiMail, published on 12 Jul 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A missing release of memory after its effective lifetime vulnerability in the Webmail of FortiMail 6.4.0 through 6.4.4 and 6.2.0 through 6.2.6 may allow an unauthenticated remote attacker to exhaust available memory via specifically crafted login requests.

Weakness: CWE-401

Which versions are affected by CVE-2021-26090?

It affects 1 product.

Products include Fortinet Fortimail.

How do I fix CVE-2021-26090?

No fix has been published for CVE-2021-26090 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-2021-26090 being exploited?

There is no known exploitation of CVE-2021-26090 in the wild and no public exploit code.

Other vulnerabilities in Fortinet FortiMail

• CVE-2026-104286 Fortinet FortiMail Path Traversal Exploited Critical 9.8
• CVE-2021-36166 Auth bypass in Fortinet FortiMail Critical 9.8
• CVE-2021-24007 SQL injection in Fortinet FortiMail Critical 9.8
• CVE-2020-9294 Auth bypass in FortiMail Critical 9.8
• CVE-2023-47539 Auth bypass in FortiMail Critical 9.0

Sources

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

Also known as GHSA-j48p-m2m2-h4m7.