CVE-2026-39407

MEDIUM

Hono has a middleware bypass via repeated slashes in serveStatic

Title source: cna

Description

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.

Scores

CVSS v3 5.3
EPSS 0.0002
EPSS Percentile 5.4%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Details

CWE
CWE-22
Status published
Products (3)
hono/hono < 4.12.11
honojs/hono < 4.12.12
npm/hono 0 - 4.12.12npm
Published Apr 08, 2026
Tracked Since Apr 08, 2026