CVE-2021-26092

Name: CVE-2021-26092
Creator: NVD / NIST
Published: 2022-02-24T03:15:43.407+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.1/10EPSS 1.06%

Last modified Jun 17, 2026

CVE-2021-26092 is a medium-severity vulnerability rated 6.1/10 on the CVSS scale. 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.. EPSS estimates a 1.06% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

6.1/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

EPSS Probability

1.06%

60.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Fortinet	Fortiproxy	>= 1.2.0, <= 1.2.9
Fortinet	Fortiproxy	2.0.0
Fortinet	Fortiproxy	2.0.1
Fortinet	Fortios	>= 5.2.10, <= 5.2.15
Fortinet	Fortios	>= 5.4.0, <= 5.4.13
Fortinet	Fortios	>= 5.6.0, <= 5.6.14
Fortinet	Fortios	>= 6.0.0, <= 6.0.12
Fortinet	Fortios	>= 6.2.0, <= 6.2.7
Fortinet	Fortios	>= 6.4.0, <= 6.4.4

References

https://fortiguard.com/psirt/FG-IR-20-199Vendor Advisory
https://fortiguard.com/psirt/FG-IR-20-199Vendor Advisory

Timeline

Published: Feb 24, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-26092?

How severe is CVE-2021-26092?

CVE-2021-26092 has a CVSS score of 6.1/10 (MEDIUM severity). The EPSS model estimates a 1.06% probability of exploitation in the next 30 days.

How do I fix CVE-2021-26092?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-26092?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST