WordPressプラグイン「LiteSpeed Cache」にクロスサイトスクリプティング（XSS）の脆弱性（CVE-2026-76579）
概要
WordPressプラグイン「LiteSpeed Cache」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 7.9 以前に影響があります。
修正版 7.9.1 への更新が推奨されます。
脆弱性の基本情報
| 脆弱性ID |
CVE-2026-76579 WF-ba236f86-0434-4030-8e14-4db3919226eb |
|---|---|
| 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 |
4.7（CVSS v3.1） CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N |
| 公開日 | 2026年9月18日 |
| 更新日 | 2026年9月19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「LiteSpeed Cache」 |
7.9 以前 | 7.9.1 | Wordfence Intelligence |
推奨対応
- WordPressプラグイン「LiteSpeed Cache」を修正版 7.9.1 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
LiteSpeed Cache <= 7.9 - Reflected Cross-Site Scripting via ESI 'esi' Parameter
The LiteSpeed Cache plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'esi' parameter in all versions up to, and including, 7.9 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 that the attacker supply a validly signed 'esi' value in the GET query string while submitting a separate attacker-controlled 'esi' payload as a POST body field, relying on PHP's default $_REQUEST merge order to have the POST value take precedence at the point of execution.
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