Hono's IPv4 address validation bypass in IP Restriction Middleware allows IP spoofing

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.

Scores

EPSS (exploitation in 30 days)

0.34% · top 72% of all CVEs (6 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: no · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.8.

Weakness

• CWE-185: Incorrect Regular Expression (opens in a new tab)All about CWE-185 and its CVEs

Affected products

• honojs · hono

  • affected < 4.11.7

Affected packages

From reviewed advisories of the GitHub Advisory Database.

• npmhonoGHSA-r354-f388-2fhh (opens in a new tab)

References (3)

• https://github.com/honojs/hono/security/advisories/GHSA-r354-f388-2fhh (opens in a new tab)x_refsource_CONFIRM
• https://github.com/honojs/hono/commit/edbf6eea8e6c26a3937518d4ed91d8666edeec37 (opens in a new tab)x_refsource_MISC
• https://github.com/honojs/hono/releases/tag/v4.11.7 (opens in a new tab)x_refsource_MISC

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisory GHSA-r354-f388-2fhh (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2026-24398](https://trackcve.app/badge/CVE-2026-24398.svg)](https://trackcve.app/cve/CVE-2026-24398)

Record last updated 27 Jan 2026, 19:20 UTC.