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

25 Oct 2026, 17:10

Type	Values Removed	Values Added
Summary		(es) Hono es un framework de aplicación web que proporciona soporte para cualquier entorno de ejecución de JavaScript. Desde la versión 4.0.0 hasta la 4.12.27, cx() en hono/css compone nombres de clase a partir de cadenas de texto simples pero marca el resultado como ya escapado sin escapar la entrada en HTML, permitiendo que valores de className no confiables utilizados en un atributo de clase JSX durante la renderización del lado del servidor rompan el atributo e inyecten marcado arbitrario. Este problema está solucionado en la versión 4.12.27.

Information

Published : 2026-07-08 17:17

Updated : 2026-10-25 17:10

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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