FlexStock – Product Stock Sync with Google Sheets for WooCommerce — CVE-2026-107711

どんな問題か

The FlexStock – Product Stock Sync with Google Sheets for WooCommerce plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'products[].post_content' parameter in all versions up to, and including, 3.17.2 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with subscriber-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This is exploitable by any Subscriber-level user because the plugin's admin_enqueue_scripts callback exposes the REST bearer token in the Dashboard page source via wp_localize_script() without a capability check, and the REST endpoint's permission_callback validates only that bearer token rather than performing a current_user_can() capability check.

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 FlexStock – Product Stock Sync with Google Sheets for WooCommerce 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。