What’s Vulnerable › Vulnerabilities
CVE-2026-44458: Hono: CSS Declaration Injection via Style Object Values in JSX SSR
- Severity: medium (CVSS 4.3 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.2% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-05-13 · updated 2026-10-26
- Weakness: CWE-74
Description
Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.18, the JSX renderer escapes style attribute object values for HTML but not for CSS. Untrusted input in a style object value or property name can therefore inject additional CSS declarations into the rendered style attribute. The impact is limited to CSS and does not allow JavaScript execution or HTML attribute breakout. This vulnerability is fixed in 4.12.18.
Affected products
- honojs hono: before 4.12.18 — fixed in 4.12.18
How to fix
Upgrade to a fixed version: honojs hono 4.12.18. Check the vendor advisory for mitigations.
References
Get alerted when CVE-2026-44458 or the next vulnerability affects your stack