XSS in WordPress
CVE-2021-39201
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)
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N.
EPSS exploit prediction
EPSS: 0.015 (73.1th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 73rd percentile — 73.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.015 · newest: 0.015 · change: 0.000
Affected products
- WordPress
- WordPress Wordpress-Develop — versions >= 5.0, < 5.8.0
- Debian Linux — versions 10.0, 11.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- hackerone.com/reports/1142140 (Permissions Required)
- github.com/WordPress/wordpress-develop/security/advisories/GHSA-wh69-25hr-h94v (Third Party Advisory)
- www.debian.org/security/2021/dsa-4985 (vendor-advisory, Third Party Advisory)
Frequently asked questions
- What is CVE-2021-39201?
- CVE-2021-39201 is a high-severity vulnerability in WordPress, classified under Cross-site Scripting. CVSS score: 7.6/10. Published 2021-09-09.
- How severe is CVE-2021-39201?
- High severity. CVSS v3 base score is 7.6 out of 10.
- Is CVE-2021-39201 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.