WordPressプラグイン「Really Simple Security – Simple and Performant Security (formerly Really Simple SSL)」にリソースの過剰消費の脆弱性（CVE-2026-88798）
概要
WordPressプラグイン「Really Simple Security – Simple and Performant Security (formerly Really Simple SSL)」にリソースの過剰消費の脆弱性が確認されました。
バージョン 9.8.2 以前に影響があります。
修正版 9.8.3 への更新が推奨されます。
脆弱性の基本情報
| 脆弱性ID |
CVE-2026-88798 WF-fbfd334c-dba4-49ec-b854-59e52236fe57 |
|---|---|
| 脆弱性の種類 | リソースの過剰消費 |
| 危険度 | 中 |
| CVSSスコア |
5.3（CVSS v3.1） CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
| 公開日 | 2026年9月16日 |
| 更新日 | 2026年9月22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「Really Simple Security – Simple and Performant Security (formerly Really Simple SSL)」 |
9.8.2 以前 | 9.8.3 | Wordfence Intelligence |
推奨対応
- WordPressプラグイン「Really Simple Security – Simple and Performant Security (formerly Really Simple SSL)」を修正版 9.8.3 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
Really Simple Security (Free) <= 9.8.2 - Unauthenticated Unbounded Option Growth
The Really Simple Security (Free) plugin for WordPress is vulnerable to Denial of Service in all versions up to, and including, 9.8.2. This is due to missing validation on client-supplied IP headers used as storage keys in the rsssl_404_cache option, allowing arbitrary values from HTTP_CLIENT_IP and HTTP_X_FORWARDED_FOR to be written as array keys without bound. This makes it possible for unauthenticated attackers to grow the rsssl_404_cache option without bound by supplying arbitrary values in spoofed client IP headers, degrading site performance when handling 404 responses.
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