CVE-2021-26092 Cross-site scripting in Fortinet FortiOS, FortiProxy

What is CVE-2021-26092?

CVE-2021-26092 is a medium-severity cross-site scripting vulnerability in Fortinet Fortios, published on 24 Feb 2022. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

Failure to sanitize input in the SSL VPN web portal of FortiOS 5.2.10 through 5.2.15, 5.4.0 through 5.4.13, 5.6.0 through 5.6.14, 6.0.0 through 6.0.12, 6.2.0 through 6.2.7, 6.4.0 through 6.4.4; and FortiProxy 1.2.0 through 1.2.9, 2.0.0 through 2.0.1 may allow a remote unauthenticated attacker to perform a reflected Cross-site Scripting (XSS) attack by sending a request to the error page with malicious GET parameters.

Weakness: CWE-79

Which versions are affected by CVE-2021-26092?

It affects 2 products.

Products include Fortinet Fortios, Fortinet Fortiproxy.

How do I fix CVE-2021-26092?

No fix has been published for CVE-2021-26092 yet. Limit exposure of the affected software until one is available.

Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.

Is CVE-2021-26092 being exploited?

There is no known exploitation of CVE-2021-26092 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-mpgj-7qvh-h4r8.