CVE-2026-44458
Hono: CSS Declaration Injection via Style Object Values in JSX SSR
CVSS Score
4.3
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-74 CWE-116 |
| Vendor | honojs |
| Product | hono |
| Published | May 13, 2026 |
Stay Ahead of the Next One
Get instant alerts for honojs hono
Be the first to know when new medium vulnerabilities affecting honojs hono are published — delivered to Slack, Telegram or Discord.
Get Free Alerts →
Free · No credit card · 60 sec setup
CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
None
Affected Versions
honojs / hono
< 4.12.18