CVE-2021-39202

Name: CVE-2021-39202
Creator: NVD / NIST
Published: 2021-09-09T22:15:09.59+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.4/10EPSS 0.79%

Last modified Jun 17, 2026

CVE-2021-39202 is a medium-severity vulnerability rated 5.4/10 on the CVSS scale. WordPress is a free and open-source content management system written in PHP and paired with a MySQL or MariaDB database. In affected versions the widgets editor introduced in WordPress 5.8 beta 1 has improper handling of HTML input in the Custom HTML feature. EPSS estimates a 0.79% chance of exploitation in the next 30 days.

Description

WordPress is a free and open-source content management system written in PHP and paired with a MySQL or MariaDB database. In affected versions the widgets editor introduced in WordPress 5.8 beta 1 has improper handling of HTML input in the Custom HTML feature. This leads to stored XSS in the custom HTML widget. This has been patched in WordPress 5.8. It was only present during the testing/beta phase of WordPress 5.8.

Metrics

CVSS 3.1

5.4/10

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

EPSS Probability

0.79%

51.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions	Update
Wordpress	Wordpress	5.8	Beta1

References

https://github.com/WordPress/wordpress-develop/security/advisories/GHSA-fr6h-3855-j297Third Party Advisory
https://hackerone.com/reports/1222797Permissions Required
https://github.com/WordPress/wordpress-develop/security/advisories/GHSA-fr6h-3855-j297Third Party Advisory
https://hackerone.com/reports/1222797Permissions Required

Timeline

Published: Sep 9, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-39202?

How severe is CVE-2021-39202?

CVE-2021-39202 has a CVSS score of 5.4/10 (MEDIUM severity). The EPSS model estimates a 0.79% probability of exploitation in the next 30 days.

How do I fix CVE-2021-39202?

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-2021-39202?

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

Scan your code now

Source: NVD / NIST