CVE-2026-56762

Hono before 4.12.12 does not validate cookie names on the write path in the setCookie(), serialize(), and serializeSigned() functions, allowing invalid characters such as control characters (e.g. \r or \n) when an application passes a user-controlled cookie name. This can produce malformed Set-Cookie header values. In modern runtimes such as Node.js and Cloudflare Workers, such invalid header values are rejected and cause a runtime error before the response is sent, so header injection or response splitting could not be reproduced; the issue primarily affects correctness and robustness, resulting in runtime errors (availability) rather than confirmed header injection.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/honojs/hono/security/advisories/GHSA-26pp-8wgv-hjvm
https://www.vulncheck.com/advisories/hono-missing-cookie-name-validation-in-setcookie

Configurations

No configuration.

History

No history.

Information

Published : 2026-06-23 13:16

Updated : 2026-06-24 13:16

NVD link : CVE-2026-56762

Mitre link : CVE-2026-56762

CVE.ORG link : CVE-2026-56762

JSON object : View

Products Affected

No product.

CWE

CWE-20

Improper Input Validation

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