WordPress Core 5.4 - 5.8 - Authenticated Stored Cross-Site Scripting

2021-09-09 00:00
Michał Bentkowski

Strategic Overview

Status
Patched in 5.4.7
Affected CoreWordPress 5.8
Affected Version5.4 – < 5.8.1 · 5 branches
CVSS7.6High
CVECVE-2021-39201
View all WordPress 5.8 vulnerabilities

Vulnerability Overview

WordPress is a free and open-source content management system written in PHP and paired with a MySQL or MariaDB database. ### Impact The issue allows an authenticated but low-privileged user (like contributor/author) to execute XSS in the editor. This bypasses the restrictions imposed on users who do not have the permission to post `unfiltered_html`. ### Patches This has been patched in WordPress 5.8, and will be pushed to older versions via minor releases (automatic updates). It's strongly recommended that you keep auto-updates enabled to receive the fix. ### References https://wordpress.org/news/category/releases/ https://hackerone.com/reports/1142140 ### For more information If you have any questions or comments about this advisory: * Open an issue in [HackerOne](https://hackerone.com/wordpress)

Technical Analysis

REMEDIATION: Update to one of the following versions, or a newer patched version: 5.4.7, 5.5.6, 5.6.5, 5.7.3, 5.8.1 --- IDENTIFIER: CWE-79 (Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

External References

Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C