CVE-2026-93981: honojs hono Cross-site Scripting

Vulnerability summary

CVE-2026-93981 is a medium (CVSS 4.7) Cross-site Scripting vulnerability in honojs hono. EPSS estimates a 0.23% chance of exploitation in the next 30 days, higher than 12.6% of scored vulnerabilities.

Timeline

1. 19-09-2026
   PublishedVulnerability first disclosed.
2. 21-09-2026
   Last modifiedVulnerability information updated.

Description

hono before 4.13.7 fails to HTML-escape plain strings rendered by hono/jsx as a child or fallback of Suspense, as a string child of ErrorBoundary alongside an asynchronous sibling, as the single child of a Context.Provider, or as the root value passed to renderToString() or renderToReadableStream() from hono/jsx/dom/server. These paths stringify their input and treat the result as already-escaped markup, so an attacker who controls such a string during server-side rendering can inject arbitrary HTML and execute script under the application's origin.

• CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.