Vulnerability · Published Jan 27, 2026 · Assigned by GitHub_M

CVE-2026-24398Hono's IPv4 address validation bypass in IP Restriction Middleware allows IP spoofing

Medium 4.8

In plain English

A medium-severity security flaw in hono from honojs. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 28% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)4.8Medium

Exploit odds (30 days)0.3%top 72.1% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to version 4.11.7, IP Restriction Middleware in Hono is vulnerable to an IP address validation bypass. The `IPV4_REGEX` pattern and `convertIPv4ToBinary` function in `src/utils/ipaddr.ts` do not properly validate that IPv4 octet values are within the valid range of 0-255, allowing attackers to craft malformed IP addresses that bypass IP-based access controls. Version 4.11.7 contains a patch for the issue.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
npm	hono	4.11.7	GHSA-r354-f388-2fhh

Affected products (as reported)

Vendor	Product	Versions
honojs	hono	< 4.11.7

Weakness: CWE-185 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

References

https://github.com/honojs/hono/security/advisories/GHSA-r354-f388-2fhh x_refsource_CONFIRM
https://github.com/honojs/hono/commit/edbf6eea8e6c26a3937518d4ed91d8666edeec37 x_refsource_MISC
https://github.com/honojs/hono/releases/tag/v4.11.7 x_refsource_MISC