What’s Vulnerable › Vulnerabilities

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

• Severity: medium (CVSS 6.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-01-27 · updated 2026-06-17
• Weakness: CWE-185

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 products

• honojs hono: before 4.11.7 — fixed in 4.11.7

How to fix

Upgrade to a fixed version: honojs hono 4.11.7. Check the vendor advisory for mitigations.

References

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

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