Everest Forms – Contact Form, Payment Form, Quiz, Survey & Custom Form Builder with AI — CVE-2026-91152

どんな問題か

The Everest Forms – Contact Form, Payment Form, Quiz, Survey & Custom Form Builder with AI plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'evf_toast_type' parameter in all versions up to, and including, 3.6.2 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. Exploitation requires the sibling evf_toast parameter to decode successfully via atob(), but this is a trivially attacker-controlled prerequisite.

自分のサイトが該当するかの確認手順

1. WordPressの管理画面にログインし、左メニュー「プラグイン」（またはテーマ）に Everest Forms – Contact Form, Payment Form, Quiz, Survey & Custom Form Builder with AI があるか確認します。
2. あれば、バージョン番号を見て「対象バージョン」に当てはまるか確認します。
3. 当てはまる場合は「更新」ボタンで修正版へ。使っていないプラグインなら削除します。更新ボタンが出ない・怖くて押せない場合は、保守会社か当社へご相談ください。