{"id":"CVE-2026-92081","sourceIdentifier":"ce714d77-add3-4f53-aff5-83d477b104bb","published":"2026-09-16T09:17:10.137","lastModified":"2026-09-16T19:40:00.317","vulnStatus":"Awaiting Analysis","cveTags":[],"descriptions":[{"lang":"en","value":"fastify is a fast and low-overhead web framework for Node.js. In versions before 5.12.5, when a route registers a response trailer via reply.trailer() and is served over HTTP/2, fastify unconditionally sets the Transfer-Encoding: chunked header, which is forbidden on HTTP/2, so Node.js throws while serializing the response headers. The exception is not caught and becomes an uncaughtException, so a single unauthenticated HTTP/2 request to any route that uses trailers crashes the server process and drops all in-flight requests, and it can be repeated on every restart. The issue is fixed in fastify 5.12.5, and users should upgrade to 5.12.5 or later. As a workaround, avoid registering response trailers with reply.trailer() on routes served over HTTP/2 until upgrading."}],"affected":[{"source":"ce714d77-add3-4f53-aff5-83d477b104bb","affectedData":[{"vendor":"fastify","product":"fastify","defaultStatus":"unaffected","packageURL":"pkg:npm/fastify","versions":[{"version":"0","lessThan":"5.12.5","versionType":"semver","status":"affected"},{"version":"5.12.5","versionType":"semver","status":"unaffected"}]}]}],"metrics":{"cvssMetricV31":[{"source":"ce714d77-add3-4f53-aff5-83d477b104bb","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":5.9,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"HIGH","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":2.2,"impactScore":3.6}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-09-16T14:00:06.966478Z","id":"CVE-2026-92081","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"ce714d77-add3-4f53-aff5-83d477b104bb","type":"Secondary","description":[{"lang":"en","value":"CWE-248"}]}],"references":[{"url":"https://cna.openjsf.org/security-advisories.html","source":"ce714d77-add3-4f53-aff5-83d477b104bb"},{"url":"https://github.com/fastify/fastify/security/advisories/GHSA-4mh8-r7rc-xpvc","source":"ce714d77-add3-4f53-aff5-83d477b104bb"}]}