Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE-2026-59895
Summary
Hono is a Web application framework that provides support for any JavaScript runtime. From 4.0.0 prior to 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.
- LOW
- NETWORK
- LOW
- CHANGED
- REQUIRED
- NONE
- LOW
- NONE
CWE-79 - Cross Site Scripting
Cross-Site Scripting, commonly referred to as XSS, is the most dominant class of vulnerabilities. It allows an attacker to inject malicious code into a pregnable web application and victimize its users. The exploitation of such a weakness can cause severe issues such as account takeover, and sensitive data exfiltration. Because of the prevalence of XSS vulnerabilities and their high rate of exploitation, it has remained in the OWASP top 10 vulnerabilities for years.
References
Advisory Timeline
- Published