CVE-2026-59895 (GCVE-0-2026-59895)

Vulnerability from cvelistv5 – Published: 2026-07-08 16:09 – Updated: 2026-07-08 19:41
VLAI
Title
Hono: Server-Side XSS via JSX Escaping Bypass in cx() Utility
Summary
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.
Severity
6.1 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-08 17:50 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
  • CWE-116 - Improper Encoding or Escaping of Output
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8083 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
honojs hono Affected: >= 4.0.0, < 4.12.27
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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