CVE-2021-26087: fortiwlc XSS — Fix

Description

An improper neutralization of input during web page generation in FortiWLC version 8.6.0, version 8.5.3 and below, version 8.4.8 and below, version 8.3.3 web interface may allow both authenticated remote attackers and non-authenticated attackers in the same network as the appliance to perform a stored cross site scripting attack (XSS) via injecting malicious payloads in different locations.

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CVSS v3.1 Score

4.3

MEDIUM

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

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

Affected Products

Vendor	Product	Versions
fortinet	fortiwlc	8.4.0 — 8.4.2
fortinet	fortiwlc	8.4.4 — 8.5.4
fortinet	fortiwlc	All
fortinet	fortiwlc	All

References

Advisories & Patches

https://fortiguard.fortinet.com/psirt/FG-IR-20-137

Frequently Asked Questions

What is CVE-2021-26087? +

An improper neutralization of input during web page generation in FortiWLC version 8.6.0, version 8.5.3 and below, version 8.4.8 and below, version 8.3.3 web interface may allow both authenticated remote attackers and non-authenticated attackers in the same network as the appliance to perform a stored cross site scripting attack (XSS) via injecting malicious payloads in different locations. It has a CVSS v3.1 base score of 4.3 (MEDIUM).

How severe is CVE-2021-26087? +

CVE-2021-26087 has a CVSS v3.1 score of 4.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2021-26087? +

CVE-2021-26087 affects products from fortinet, specifically: fortiwlc. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2021-26087? +

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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CVE-2021-26087