WordPressプラグイン「Relevanssi – A Better Search」にクロスサイトスクリプティング（XSS）の脆弱性（CVE-2026-19985）
概要
WordPressプラグイン「Relevanssi – A Better Search」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 4.28.1 以前に影響があります。
修正版 4.28.2 への更新が推奨されます。
脆弱性の基本情報
| 脆弱性ID |
CVE-2026-19985 WF-d07fe28c-f76e-42b2-b894-be316004235a |
|---|---|
| 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 |
6.1（CVSS v3.1） CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| 公開日 | 2026年9月10日 |
| 更新日 | 2026年9月11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「Relevanssi – A Better Search」 |
4.28.1 以前 | 4.28.2 | Wordfence Intelligence |
推奨対応
- WordPressプラグイン「Relevanssi – A Better Search」を修正版 4.28.2 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
Relevanssi <= 4.28.1 - Reflected Cross-Site Scripting
The Relevanssi – A Better Search plugin for WordPress is vulnerable to Reflected Cross-Site Scripting in versions up to, and including, 4.28.1 via the 's', 'post_types', and 'orderby' request parameters. This is due to insufficient input sanitization and output escaping in the relevanssi_debug_array() function in lib/debug.php, which dumps user-supplied query variables through print_r() inside a <pre> block without HTML escaping. The debug path is enabled by supplying the relevanssi_debug=on request parameter when the administrator has previously enabled the 'Debugging mode' setting; the gate itself is a configuration check with no capability, nonce, or logged-in check (the vendor explicitly suppresses nonce verification on that line). 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 specially crafted link.
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