CVE-2026-39409 MEDIUM

CVE-2026-39409: Hono has incorrect IP matching in ipRestriction() for IPv4-mapped IPv6 addresses

Vendor Honojs
Product hono
Weakness CWE-180
Published April 8, 2026
Last update April 8, 2026
View on NVD All CVEs

CVSS base score

6.3/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality —
Integrity —

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

What the vulnerability does

01Description

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.12, ipRestriction() does not canonicalize IPv4-mapped IPv6 client addresses (e.g. ::ffff:127.0.0.1) before applying IPv4 allow or deny rules. In environments such as Node.js dual-stack, this can cause IPv4 rules to fail to match, leading to unintended authorization behavior. This vulnerability is fixed in 4.12.12.

Key dates

02Disclosure timeline

April 8, 2026 CVE published
April 8, 2026 Record updated