GitHub Advisoryadvisory · npm
GHSA-92pp-h63x-v22m @hono/node-server: Middleware bypass via repeated slashes in serveStatic
MEDIUM
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
- https://github.com/honojs/node-server/security/advisories/GHSA-92pp-h63x-v22m web
- https://nvd.nist.gov/vuln/detail/CVE-2026-39406 advisory
- https://github.com/honojs/node-server/commit/025c30f55d589ddbe6048b151d77e904f67a8cc2 web
- https://github.com/honojs/node-server package
- https://github.com/honojs/node-server/releases/tag/v1.19.13 web