Medium 6.1Published Jul 8, 2026

CVE-2026-59895Hono is a Web application framework that provides support for any JavaScript runtime.

Updated under an hour ago (2026-10-19 07:00 UTC)

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Every CVE for hono

Exploited in the last 30 days

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.0.0 before 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.

CVSS: 6.1 MEDIUM (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Weakness (CWE): CWE-79, CWE-116
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Not given
NVD analysis: Analyzed
Record last updated: Jul 10, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

hono hono hono:hono	from 4.0.0 before 4.12.27	NVD

References

https://github.com/honojs/hono/commit/cd3f6f7194f0e5c9d4b26ae0cf232018d0f388fcpatch
https://github.com/honojs/hono/releases/tag/v4.12.27release-notes
https://github.com/honojs/hono/security/advisories/GHSA-w62v-xxxg-mg59vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.