PT-2026-51516 · Hono · Hono

Athuljayaram · Published 2026-06-23 · Updated 2026-06-23 · CVE-2026-56762

NVD

CVSS v3.1

5.3

Medium

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

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 ) 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.

Fix

Weakness Enumeration

CWE-113

Related Identifiers

CVE-2026-56762

Affected Products

Hono

References · 3

• https://github.com/honojs/hono/security/advisories/GHSA-26pp-8wgv-hjvm · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-56762 · Security Note
• https://vulncheck.com/advisories/hono-missing-cookie-name-validation-in-setcookie · Note