{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-59895","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-07-07T16:40:07.983Z","datePublished":"2026-07-08T16:09:51.273Z","dateUpdated":"2026-07-08T19:41:04.292Z"},"containers":{"cna":{"title":"Hono: Server-Side XSS via JSX Escaping Bypass in cx() Utility","problemTypes":[{"descriptions":[{"cweId":"CWE-79","lang":"en","description":"CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-116","lang":"en","description":"CWE-116: Improper Encoding or Escaping of Output","type":"CWE"}]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":6.1,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"LOW","privilegesRequired":"NONE","scope":"CHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","version":"3.1"}}],"references":[{"name":"https://github.com/honojs/hono/security/advisories/GHSA-w62v-xxxg-mg59","tags":["x_refsource_CONFIRM"],"url":"https://github.com/honojs/hono/security/advisories/GHSA-w62v-xxxg-mg59"},{"name":"https://github.com/honojs/hono/commit/cd3f6f7194f0e5c9d4b26ae0cf232018d0f388fc","tags":["x_refsource_MISC"],"url":"https://github.com/honojs/hono/commit/cd3f6f7194f0e5c9d4b26ae0cf232018d0f388fc"},{"name":"https://github.com/honojs/hono/releases/tag/v4.12.27","tags":["x_refsource_MISC"],"url":"https://github.com/honojs/hono/releases/tag/v4.12.27"}],"affected":[{"vendor":"honojs","product":"hono","versions":[{"version":">= 4.0.0, < 4.12.27","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-07-08T16:09:51.273Z"},"descriptions":[{"lang":"en","value":"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."}],"source":{"advisory":"GHSA-w62v-xxxg-mg59","discovery":"UNKNOWN"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-08T17:50:18.277447Z","id":"CVE-2026-59895","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-07-08T19:41:04.292Z"}}]}}