CVE-2026-126359
Hono: `css` helper does not escape a closing tag split between the template and an interpolated value, allowing HTML injection
Description
Hono is a Web application framework that provides support for any JavaScript runtime. From 3.12.0 until 4.13.16, the css helper in hono/css escapes interpolated string values separately and therefore fails to neutralize a closing style tag when < ends the template text or a preceding value and / begins the next attacker-controlled value. During server-side rendering, the combined output can close the <Style /> element early and cause the remainder of the interpolated value to be interpreted as HTML. Applications that place an untrusted string immediately after < in a css template, including adjacent untrusted interpolations, can expose viewers to attacker-controlled HTML or script and information accessible to that page. Other uses of the css helper are not affected. This issue is fixed in version 4.13.16.
INFO
Published Date :
Nov. 12, 2026, 10:22 p.m.
Last Modified :
Nov. 12, 2026, 10:22 p.m.
Remotely Exploit :
Yes !
Source :
GitHub_M
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | LOW | MITRE-CVE |
Solution
- Update Hono to version 4.13.16 or later.
- Avoid untrusted strings in css template interpolations.
- Sanitize interpolated string values before use.
- Review application usage of the css helper function.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-126359 vulnerability anywhere in the article.