Echo vulnerable to Reflected Cross-Site Scripting (XSS) via unsanitized JSONP callback in Context.JSONP / Context.JSONPBlob

影響: go:github.com/labstack/echo/v5 < 5.4.0 → 5.4.0, go:github.com/labstack/echo/v4 < 4.16.0 → 4.16.0

The Context.JSONP, Context.JSONPBlob, and internal jsonPBlob helper in context.go directly concatenate the caller-supplied callback parameter into a JavaScript response without any validation, escaping, or allow-listing. This creates a high-impact reflected XSS that can be triggered by any route passing attacker-controlled data (query string, form, header, path param, etc.) into the callback. Present in current master and v5.1.0 (latest release). Vulnerable Code (verbatim) go func (c Context) j…

GitHub Advisory Databaseで読む

2026/10/29 04:54、GitHub Advisory Databaseが「Echo vulnerable to Reflected Cross-Site Scripting (XSS) via unsanitized JSONP callback in Context.JSONP / Context.JSONPBlob」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: Go、GitHub。CVE: CVE-2026-118652。