CVE-2026-44458CWE-116CWE-74

Hono: CSS Declaration Injection via Style Object Values in JSX SSR

Medium · published May 13, 2026

CVSS v3.1
4.3
EPSS
0%
Percentile
25.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
4.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
CVSS v4.0
Not supplied
EPSS
0.00335 · 25.7th percentile
Weaknesses
CWE-116 · Improper Encoding or Escaping of Output; CWE-74 · Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
Published
2026-05-13T15:01Z
EPSS history
Timeline
  • 13 MAY 15:01Z
    Hono: CSS Declaration Injection via Style Object Values in JSX SSR
    cvelistv5