blogsafe.org My Downloads

BlogSafe.org

WordPress CVEs

Search and review WordPress-related vulnerability records.

← Back to CVE list

CVE-2026-15826

CRITICAL 9.8 CVSS 3.1
Published
August 15, 2026
Last modified
August 20, 2026
NVD status
Deferred
Reported by
security@wordfence.com
Weakness
CWE-704
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Description

The User Profile Builder plugin for WordPress is vulnerable to Authentication Bypass via Type Confusion in versions up to, and including, 3.16.4. This is due to the wppb_log_in_user() function calling absint() on the return value of wp_insert_user() before performing an is_wp_error() check — when a registration is submitted with a 61–70 character username, WordPress core rejects it with a WP_Error object, but absint() coerces that object to the integer 1 before the error check can short-circuit execution, causing the plugin to bind and return a transient-backed autologin nonce tied to user ID 1. This makes it possible for unauthenticated attackers to log in as the site's Administrator account (user ID 1), resulting in full administrative takeover of the site.

Affected WordPress components

  • User Profile Builder – Beautiful User Registration Forms, User Profiles & User Role Editor Plugin · profile-builder
    Confirmed match Active
    Up to and including 3.16.4
    View on WordPress.org

A confirmed match is backed by the plugin or theme slug. A possible match is based on the product name only and should be verified.

Affected products and versions

  • cozmoslabs User Profile Builder – Beautiful User Registration Forms, User Profiles & User Role Editor — Up to and including 3.16.4

References

  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/profile-builder/tags/3.16.4/features/functions.php#L1481
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/profile-builder/tags/3.16.4/front-end/class-formbuilder.php#L262
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/profile-builder/tags/3.16.4/front-end/class-formbuilder.php#L364
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/profile-builder/tags/3.16.4/front-end/class-formbuilder.php#L742
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/profile-builder/tags/3.16.4/front-end/class-formbuilder.php#L945
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/profile-builder/tags/3.16.4/front-end/default-fields/username/username.php#L28
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/profile-builder/tags/3.16.4/front-end/default-fields/username/username.php#L49
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/changeset/3609855/profile-builder
  • www.wordfence.com https://www.wordfence.com/threat-intel/vulnerabilities/id/9f606fba-f779-42ea-a160-6c3b20dc5e79?source=cve
  • nvd.nist.gov Official NVD record