Incorrect Behavior Order: Validate Before Canonicalize Affecting hono package, versions <4.12.12
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- published8 Apr 2026
- disclosed8 Apr 2026
- creditr74tech
Introduced: 8 Apr 2026
NewCVE-2026-39409 (opens in a new tab)Common Vulnerabilities and Exposures (CVE) are common identifiers for publicly known security vulnerabilities
Common Weakness Enumeration (CWE) is a category system for software weaknesses
How to fix?
Upgrade hono to version 4.12.12 or higher.
Overview
hono is an Ultrafast web framework for the Edges
Affected versions of this package are vulnerable to Incorrect Behavior Order: Validate Before Canonicalize in the ipRestriction function. An attacker can bypass access restrictions by sending requests from IPv4-mapped IPv6 addresses, which are not properly matched against IPv4 allow or deny rules.