CVE-2026-59895

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.0.0 before 4.12.27, cx() in hono/css composes class names from plain strings but marks the result as already escaped without HTML-escaping the input, allowing untrusted className values used in a JSX class attribute during server-side rendering to break out of the attribute and inject arbitrary markup. This issue is fixed in version 4.12.27.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/honojs/hono/commit/cd3f6f7194f0e5c9d4b26ae0cf232018d0f388fc	Patch
https://github.com/honojs/hono/releases/tag/v4.12.27	Release Notes
https://github.com/honojs/hono/security/advisories/GHSA-w62v-xxxg-mg59	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:hono:hono:*:*:*:*:*:node.js:*:*

History

No history.

Information

Published : 2026-07-08 17:17

Updated : 2026-07-10 19:53

NVD link : CVE-2026-59895

Mitre link : CVE-2026-59895

CVE.ORG link : CVE-2026-59895

JSON object : View

Products Affected

hono

hono

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CWE-116

Improper Encoding or Escaping of Output

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