CVE-2026-109955

Hono from 4.12.4 before 4.13.11 contains a middleware bypass vulnerability in serveStatic that allows unauthenticated attackers to skip prefix middleware by exploiting double path decoding. Attackers can send malformed percent-encoded paths that the router matches in encoded form, reaching static files without authentication checks running.

Hono from 4.12.4 before 4.13.11 contains a middleware bypass vulnerability in serveStatic that allows unauthenticated attackers to skip prefix middleware by exploiting double path decoding. Attackers can send malformed percent-encoded paths that the router matches in encoded form, reaching static files without authentication checks running.

Hono from 4.12.4 before 4.13.11 contains a middleware bypass vulnerability in serveStatic that allows unauthenticated attackers to skip prefix middleware by exploiting double path decoding. Attackers can send malformed percent-encoded paths that the router matches in encoded form, reaching static files without authentication checks running.

Hono from 4.12.4 before 4.13.11 contains a middleware bypass vulnerability in serveStatic that allows unauthenticated attackers to skip prefix middleware by exploiting double path decoding. Attackers can send malformed percent-encoded paths that the router matches in encoded form, reaching static files without authentication checks running.

Hono from 4.12.4 before 4.13.11 contains a middleware bypass vulnerability in serveStatic that allows unauthenticated attackers to skip prefix middleware by exploiting double path decoding. Attackers can send malformed percent-encoded paths that the router matches in encoded form, reaching static files without authentication checks running.

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.12.4 until 4.13.11, serveStatic can interpret a malformed percent-encoded path differently from upstream routing middleware and bypass protection for a static prefix. The root cause is serveStatic decodes a routed request path a second time before filesystem lookup. The attack mechanism is malformed percent encoding survives the first routing interpretation and becomes a protected path only during the later static-file decode. The affected component is serveStatic. The trigger conditions are an application protects a static prefix with upstream middleware and serveStatic receives an attacker-controlled malformed percent-encoded path. The impact is unauthorized disclosure of a static file that upstream middleware was intended to protect. The issue does not permit traversal outside the configured static root. This issue is fixed in version 4.13.11.