GitHub Advisoryadvisory · npm

GHSA-92pp-h63x-v22m @hono/node-server: Middleware bypass via repeated slashes in serveStatic

MEDIUM Published 2026-04-08 Modified 2026-04-08 Official page ↗
Aliases
CVE-2026-39406
Ecosystem
npm
Packages
@hono/node-server
Severity
Moderate
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Weaknesses
CWE-22
Reviewed
2026-04-08

Affected packages

• npm @hono/node-server: < 1.19.13 → fixed in 1.19.13

Description

Summary A path handling inconsistency in `serveStatic` allows protected static files to be accessed by using repeated slashes (`//`) in the request path. When route-based middleware (e.g., `/admin/*`) is used for authorization, the router may not match paths containing repeated slashes, while `serveStatic` resolves them as normalized paths. This can lead to a middleware bypass. Details The routing layer and `serveStatic` handle repeated slashes differently. For example: • `/admin/secret.txt` => matches `/admin/*` • `//admin/secret.txt` => may not match `/admin/*` This inconsistency allows a request such as: ``` GET //admin/secret.txt ``` to bypass middleware registered on `/admin/*` and access protected files. Impact An attacker can access static files that are intended to be protected by route-based middleware by using repeated slashes in the request path. This can lead to unauthorized access to sensitive files under the static root. This issue affects applications that rely on `serveStatic` together with route-based middleware for access control.

Related

Alias · CVE (1)

  • CVE-2026-39406 @hono/node-server allows running the Hono application on Node.js. vulnerability

Weakness · CWE (1)

  • CWE-22 Improper Limitation of a Pathname to a Restricted Directory weakness

References