What’s Vulnerable › Vulnerabilities

CVE-2026-59896: hono/jsx does not isolate context per request, leading to cross-request data disclosure

• Severity: medium (CVSS 6.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-07-08 · updated 2026-10-25
• Weakness: CWE-362

Description

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.11.8 before 4.12.27, hono/jsx did not isolate context values per request during server-side rendering, allowing createContext, useContext, jsxRenderer, or useRequestContext data from a different in-flight request to be used after an await in an async component. This issue is fixed in version 4.12.27.

Affected products

• honojs hono: from 4.11.8 before 4.12.27 — fixed in 4.12.27

How to fix

Upgrade to a fixed version: honojs hono 4.12.27. Check the vendor advisory for mitigations.

References

• https://github.com/honojs/hono/commit/fab3b13639339cbd5ba1166a5b23d9ac30c5f64f
• https://github.com/honojs/hono/releases/tag/v4.12.27
• https://github.com/honojs/hono/security/advisories/GHSA-hvrm-45r6-mjfj

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