Cross-site scripting in hono - CVE-2026-126359
Published: November 10, 2026 / Updated: November 13, 2026
Vulnerability identifier: #VU164379
CSH Severity: Low
CVSS v4: 2.1 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N]
CVE-ID: CVE-2026-126359
CWE-ID: CWE-79
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to disclose information available to a rendered page through injected browser script.
The vulnerability exists due to improper neutralization of closing tags across template boundaries in the hono/css css helper when joining individually escaped values with preceding text ending in <. A remote attacker can supply an interpolated value beginning with /style> followed by malicious HTML to produce </style>, close the style element early, and execute script that exposes page information when a user views the server-rendered page.
Affected software
hono
How to mitigate CVE-2026-126359
Install security update from vendor's website.
hono - update to 4.13.16