CVE-2026-71850: honojs hono

Vulnerability summary

CVE-2026-71850 is a medium (CVSS 4.8) vulnerability in honojs hono. EPSS estimates a 0.27% chance of exploitation in the next 30 days, higher than 17.6% of scored vulnerabilities.

Timeline

1. 07-08-2026
   PublishedVulnerability first disclosed.
2. 10-08-2026
   Last modifiedVulnerability information updated.

Description

Hono is a Web application framework that provides support for any JavaScript runtime. From 3.8.0 to 4.12.33, memo() from hono/jsx retains the result of a server side render and reuses it for later renders with comparator equal props, and request scoped values read inside the component take no part in that comparison, so a response can contain HTML rendered for another user's request. Components wrapped with memo() are compared by props alone; values read implicitly during rendering, such as JSX Context through createContext() and useContext(), useRequestContext() from hono/jsx-renderer, and getContext() from hono/context-storage, do not participate, and the retained result lives as long as the wrapped component, so it outlives the request that produced it. A user may receive a response containing HTML rendered for another user when both render the same memoized component with comparator equal props on the same warm instance, which may disclose another user's account or profile data, disclose request scoped secrets embedded in HTML such as CSRF tokens, or expose role specific content to users who should not receive it. This issue is fixed in version 4.12.34.

• CWE-488Exposure of Data Element to Wrong SessionThe product does not sufficiently enforce boundaries between the states of different sessions, causing data to be provided to, or used by, the wrong session.