fast-uri vulnerable to URI scheme spoofing via percent-encoded scheme decoding

影響: npm:fast-uri < 2.4.8 → 2.4.8, npm:fast-uri >= 3.0.0, < 3.1.9 → 3.1.9, npm:fast-uri >= 4.0.0, < 4.2.3 → 4.2.3

fast-uri percent-decodes the scheme component with the legacy global unescape() before validating it, so an input whose decoded scheme is a valid but dangerous token is emitted as a live scheme. RFC 3986 section 3.1 does not allow percent-encoding in a scheme, so no RFC or WHATWG parser treats such input as having that scheme, but fast-uri does. For example, normalize('%6Aavascript:alert(1)') returns javascript:alert(1), resolve('https://a.example/', '%6Aavascript:alert(1)') returns javascript:…

GitHub Advisory Databaseで読む

2026/10/24 06:41、GitHub Advisory Databaseが「fast-uri vulnerable to URI scheme spoofing via percent-encoded scheme decoding」を公開しました (種別: 脆弱性アドバイザリ)。重大度は「警告」(medium) です。関連する技術: JavaScript / Node.js。CVE: CVE-2026-110306。