CVE-2026-15826
User Profile Builder – Beautiful User Registration Forms, User Profiles & User Role Editor に報告された脆弱性
概要
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.
影響を受けるバージョン
- 0以上 〜 3.16.4以下
対処方法
User Profile Builder – Beautiful User Registration Forms, User Profiles & User Role Editor を 3.16.5 以降に更新してください。これで本脆弱性は解消します。
あなたのサイトは大丈夫ですか?
URLを入力するだけで、実際に使われているプラグインを検出し、 このデータベースと突き合わせて既知の脆弱性が残っていないかを確認できます。登録不要・無料です。
30秒で無料診断する参照
- https://plugins.trac.wordpress.org/browser/profile-builder/tags/3.16.4/features/functions.php#L1481
- https://plugins.trac.wordpress.org/browser/profile-builder/tags/3.16.4/front-end/class-formbuilder.php#L262
- https://plugins.trac.wordpress.org/browser/profile-builder/tags/3.16.4/front-end/class-formbuilder.php#L364
- https://plugins.trac.wordpress.org/browser/profile-builder/tags/3.16.4/front-end/class-formbuilder.php#L742
- https://plugins.trac.wordpress.org/browser/profile-builder/tags/3.16.4/front-end/class-formbuilder.php#L945
- https://plugins.trac.wordpress.org/browser/profile-builder/tags/3.16.4/front-end/default-fields/username/username.php#L28
- https://plugins.trac.wordpress.org/browser/profile-builder/tags/3.16.4/front-end/default-fields/username/username.php#L49
- https://plugins.trac.wordpress.org/changeset/3609855/profile-builder