CVE-2021-26102

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.

CVSS v3.1 Score

9.8

CRITICAL

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

Weakness Type (CWE)

CWE-305 CWE-305

CWE-22 Path Traversal

Affected Products

Vendor	Product	Versions
fortinet	fortiwan	4.4.0 — 4.5.8

References

Advisories & Patches

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

Frequently Asked Questions

What is CVE-2021-26102? +

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. It has a CVSS v3.1 base score of 9.8 (CRITICAL).

How severe is CVE-2021-26102? +

CVE-2021-26102 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

What products are affected by CVE-2021-26102? +

CVE-2021-26102 affects products from fortinet, specifically: fortiwan. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2021-26102? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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