CVE-2026-39407 PUBLISHED

Hono has a middleware bypass via repeated slashes in serveStatic

Assigner: GitHub_M
Reserved: 07.04.2026 Published: 08.04.2026 Updated: 08.04.2026

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.12, 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. This vulnerability is fixed in 4.12.12.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
CVSS Score: 5.3

Product Status

Vendor honojs
Product hono
Versions
  • Version < 4.12.12 is affected

References

Problem Types

  • CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') CWE