CVE-2026-103962: User Frontend reflected cross-site scripting (XSS) vulnerability
medium 6.1 published 2026-10-31 · updated 2026-11-02
- Affected versions
- 4.3.13 and older
- Fixed in
- 4.3.14 *
- Latest version
- 4.3.14
- Severity
- Medium · CVSS 6.1
- Active installs
- 20,000+
- Type
- Reflected cross-site scripting (XSS)
* The source does not name a fixed version; this is the first wordpress.org release after the last affected version.
What an attacker needs
- Access: None. No account or login is needed.
- Interaction: It also needs someone on the site (often an admin) to click a link, open a page or submit a form the attacker prepared.
CVSS vector (score by Wordfence): CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
What to do now
- Update User Frontend to 4.3.14 or newer: Dashboard → Updates, or Plugins → “update now”.
- If you cannot update right away, deactivate it until you can.
- Turn on auto-updates for it: Plugins → “Enable auto-updates” on its row.
- Not sure which version you run? Check your version against every known User Frontend issue.
With WP-CLI:
wp plugin get wp-user-frontend --field=version. - If you ran an affected version and something looks off (new admin users, spam pages, redirects), run the free scan below.
The advisory
The User Frontend – Membership, User Registration, User Profile, User Directory & Content Restriction with Frontend Post Submission plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'field_attr[required]' parameter in all versions up to, and including, 4.3.13 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link. The nonce check on the wpuf_get_child_cat AJAX action is not an effective security barrier because the wpuf_nonce value is publicly localized to every anonymous visitor of any page containing a WPUF shortcode, making it freely harvestable by an unauthenticated attacker.
References
- NVD CVE-2026-103962 nvd.nist.gov
- Wordfence advisory www.wordfence.com
- Code change (fix) plugins.trac.wordpress.org
- Plugin source plugins.trac.wordpress.org
Related
Ran an affected version? Check your site for signs of a hack
The free scan reads the public side of your site and looks for spam pages, hidden redirects, injected scripts and blacklist entries. No login, no install, about a minute.
Where this data comes from
- CVE record, score and references: NIST National Vulnerability Database (NVD), checked 2026-11-04. This product uses data from the NVD API but is not endorsed or certified by the NVD.
- Versions and install counts: wordpress.org/plugins/wp-user-frontend (Plugins API), fetched 2026-11-04.
- The summary, “what an attacker needs” and “what to do” sections are our plain-English reading of the record and the plugin's release history; the quoted description is the record's own text. Spot an error? Email Daniel.