CVE-2026-56762

Hono - Missing Cookie Name Validation in setCookie()

Published Jun 23, 2026 CVSS 4.0 · 6.9 Medium EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-26pp-8wgv-hjvm Hono missing validation of cookie name on write path in setCookie()
History
Type Values Removed Values Added
Weaknesses CWE-113 CWE-20
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description 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.
Title Hono - Missing Cookie Name Validation in setCookie()
First Time appeared Hono
Hono hono
Weaknesses CWE-113
CPEs cpe:2.3:a:hono:hono:*:*:*:*:*:node.js:*:*
Vendors & Products Hono
Hono hono
References
Metrics cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L'}

cvssV4_0

{'score': 6.9, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Jun 24, 2026, 11:17 AM
Reserved
Jun 22, 2026, 9:55 PM
Status
Deferred
Published
Jun 23, 2026, 1:16 PM
Modified
Jun 24, 2026, 1:16 PM