CVE-2026-109447: User Profile Builder privilege escalation vulnerability
high 8.1 published 2026-10-16
- Affected versions
- 4.0.3 and older
- Fixed in
- 4.0.4 *
- Latest version
- 4.0.6
- Severity
- High · CVSS 8.1
- Active installs
- 40,000+
- Type
- Privilege escalation
* 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.
CVSS vector (score by Wordfence): CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
What to do now
- Update User Profile Builder to 4.0.4 or newer (the latest is 4.0.6): 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 Profile Builder issue.
With WP-CLI:
wp plugin get profile-builder --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 Profile Builder – Beautiful User Registration Forms, User Profiles & User Role Editor plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 4.0.3 via the `role` parameter handled by the `wppb_add_meta_to_user_on_activation()` function. The vulnerability exists because the activation handler passes the attacker-supplied role value directly to `WP_User::set_role()` with no allow-list validation, and the 4.0.3 reserved-name check exempts pre-existing form fields from the block, allowing a legacy field with meta-name `role` to persist and bridge attacker-controlled request input into the serialized signup record stored in `wp_signups`. This makes it possible for unauthenticated attackers to gain a fully activated WordPress administrator account by submitting `role=administrator` through the public `[wppb-register]` shortcode form and subsequently clicking the confirmation activation link. Exploitation requires the site to have a legacy form field with meta-name `role` carried over from before the 4.0.3 upgrade, email confirmation enabled, and open user registration — all stable site-state conditions once established.
References
- NVD CVE-2026-109447 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/profile-builder (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.