CVE-2026-39407CWE-22

Hono has a middleware bypass via repeated slashes in serveStatic

Medium · published April 8, 2026

CVSS v3.1
5.3
EPSS
0%
Percentile
38.1
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
5.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
CVSS v4.0
Not supplied
EPSS
0.00450 · 38.1th percentile
Weakness
CWE-22 · Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Published
2026-04-08T14:41Z
EPSS history
Timeline
  • 08 APR 14:41Z
    Hono has a middleware bypass via repeated slashes in serveStatic
    cvelistv5