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…

Read on GitHub Advisory Database

On 10/29/2026, 04:54 AM, GitHub Advisory Database published "Echo vulnerable to Reflected Cross-Site Scripting (XSS) via unsanitized JSONP callback in Context.JSONP / Context.JSONPBlob" (type: Advisory). Severity is "Medium" (medium). Related technologies: Go, GitHub. CVE: CVE-2026-118652.