CVE-2021-26102

Name: CVE-2021-26102
Creator: NVD / NIST
Published: 2024-12-19T14:15:05.38+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.1/10EPSS 16.36%

Last modified Jun 17, 2026

CVE-2021-26102 is a critical-severity vulnerability rated 9.1/10 on the CVSS scale. A relative path traversal vulnerability (CWE-23) in FortiWAN version 4.5.7 and below, 4.4 all versions may allow a remote non-authenticated attacker to delete files on the system by sending a crafted POST request. In particular, deleting specific configuration files will reset the Admin password to its default value.. EPSS estimates a 16.36% chance of exploitation in the next 30 days.

Description

A relative path traversal vulnerability (CWE-23) in FortiWAN version 4.5.7 and below, 4.4 all versions may allow a remote non-authenticated attacker to delete files on the system by sending a crafted POST request. In particular, deleting specific configuration files will reset the Admin password to its default value.

Metrics

CVSS 3.1

9.1/10

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

EPSS Probability

16.36%

96.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Fortinet	Fortiwan	>= 4.4.0, < 4.5.8

References

https://fortiguard.fortinet.com/psirt/FG-IR-21-048Vendor Advisory

Timeline

Published: Dec 19, 2024
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2021-26102?

How severe is CVE-2021-26102?

CVE-2021-26102 has a CVSS score of 9.1/10 (CRITICAL severity). The EPSS model estimates a 16.36% probability of exploitation in the next 30 days.

How do I fix CVE-2021-26102?

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-2021-26102?

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

Scan your code now

Source: NVD / NIST