cvedb.io
CVE-2026-56762
MEDIUM · CVSS 5.3
EPSS exploitation probability: 17%
Published 2026-06-23T13:16:46.813 · Last modified 2026-06-24T13:16:37.203

Summary

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.

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.