WordPressテーマ「Avada | Website Builder For WordPress & WooCommerce」など2製品に認可の欠如の脆弱性（CVE-2026-18431）
概要
WordPressテーマ「Avada | Website Builder For WordPress & WooCommerce」に認可の欠如の脆弱性が確認されました。
バージョン 7.16 以前に影響があります。
修正版 7.16.1 への更新が推奨されます。
WordPressプラグイン「Avada (Fusion) Builder」に認可の欠如の脆弱性が確認されました。
バージョン 3.16 以前に影響があります。
修正版 3.16.1 への更新が推奨されます。
脆弱性の基本情報
| 脆弱性ID |
CVE-2026-18431 WF-5bef5bd3-8ec9-4a5b-bcdd-98952c7ef390 |
|---|---|
| 脆弱性の種類 | 認可の欠如 |
| 危険度 | 重大 |
| CVSSスコア |
9.8（CVSS v3.1） CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| 公開日 | 2026年8月25日 |
| 更新日 | 2026年8月26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テーマ「Avada | Website Builder For WordPress & WooCommerce」 |
7.16 以前 | 7.16.1 | Wordfence Intelligence |
| WordPressプラグイン「Avada (Fusion) Builder」 |
3.16 以前 | 3.16.1 | Wordfence Intelligence |
推奨対応
- WordPressテーマ「Avada | Website Builder For WordPress & WooCommerce」を修正版 7.16.1 またはそれ以降の公式最新版へ更新してください。
- WordPressプラグイン「Avada (Fusion) Builder」を修正版 3.16.1 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
Avada <= 7.16 and Fusion Builder <= 3.16 - Unauthenticated Remote Code Execution via Arbitrary File Write
The Avada theme for WordPress is vulnerable to Arbitrary File Write in all versions up to, and including, 7.16 when the Fusion Builder plugin is installed and active in versions up to, and including, 3.16. This is due to a chain of authorization and input validation weaknesses across the two components that makes it possible for unauthenticated attackers to write attacker-controlled files to the server. This can be used to create and execute arbitrary PHP files, resulting in remote code execution and complete site compromise. Successful exploitation requires both Avada and Fusion Builder to be installed and active, as well as certain administrator-authored content to be present.
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