WordPressプラグイン「Post Snippets – Custom WordPress Code Snippets Customizer」にクロスサイトスクリプティング（XSS）の脆弱性（CVE-2026-77871）
概要
WordPressプラグイン「Post Snippets – Custom WordPress Code Snippets Customizer」にクロスサイトスクリプティング（XSS）の脆弱性が確認されました。
バージョン 4.2.4 以前に影響があります。
修正版 4.2.5 への更新が推奨されます。
脆弱性の基本情報
| 脆弱性ID |
CVE-2026-77871 WF-a46c37f4-245d-423f-bdad-296fdf377ecc |
|---|---|
| 脆弱性の種類 | クロスサイトスクリプティング（XSS） |
| 危険度 | 中 |
| CVSSスコア |
6.4（CVSS v3.1） CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N |
| 公開日 | 2026年10月27日 |
影響を受ける製品
| 製品 | 影響を受けるバージョン | 修正版 | 出典 |
|---|---|---|---|
| WordPressプラグイン「Post Snippets – Custom WordPress Code Snippets Customizer」 |
4.2.4 以前 | 4.2.5 | Wordfence Intelligence |
推奨対応
- WordPressプラグイン「Post Snippets – Custom WordPress Code Snippets Customizer」を修正版 4.2.5 またはそれ以降の公式最新版へ更新してください。
情報元の原文
Wordfence Intelligence
Post Snippets <= 4.2.4 - Authenticated (Contributor+) Stored Cross-Site Scripting via Shortcode Attributes
The Post Snippets – Custom WordPress Code Snippets Customizer plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Shortcode Attributes in all versions up to, and including, 4.2.4 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. Entity-encoded payloads such as <script>...</script> survive WordPress's wp_kses_post on-save sanitization because kses does not decode HTML entities, and are only converted back into executable HTML tags at render time by the plugin's own shortcode filter. This requires snippet shortcodes to be enabled.
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