CVE-2026-15826

Received
Published: 15 Aug 2026, 06:38
Last modified:15 Aug 2026, 06:38

Vulnerability Summary

Overall Risk (default)
high
70/100
CVSS Score
9.8 CRITICAL
v3.1 (cve.org)
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

15 Aug 2026, 06:38
Published
Vulnerability first disclosed

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.

CVSS Metrics

  • v3.1CRITICALScore: 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Techniques & Countermeasures

  • CWE-704Incorrect Type Conversion or Cast

    The product does not correctly convert an object, resource, or structure from one type to a different type.

Affected Systems

  • cozmoslabsuser profile builder – beautiful user registration forms, user profiles & user role editor

    ≤ 3.16.4

References (9)