{"id":"CVE-2026-92081","title":"fastify is a fast and low-overhead web framework for Node.js","summary":"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…","severity":"medium","cvss":5.9,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-248"],"vendor":"fastify","product":"fastify","affected":["fastify < 5.12.5"],"published":"2026-09-16","updated":"2026-09-16","sourceUpdated":"2026-09-16T19:40:00.317","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-92081","references":[{"url":"https://cna.openjsf.org/security-advisories.html","label":"ce714d77-add3-4f53-aff5-83d477b104bb"},{"url":"https://github.com/fastify/fastify/security/advisories/GHSA-4mh8-r7rc-xpvc","label":"ce714d77-add3-4f53-aff5-83d477b104bb"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-92081.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-92081"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2535071"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-92081"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-92081"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-09-16T14:00:06.966478Z"},"ingestedAt":"2026-09-16T09:53:11.601Z","epss":0.00395,"epssPercentile":0.33419,"slug":"CVE-2026-92081","body":"## Overview\n\nfastify 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux AI (RHEL AI) 3, Red Hat OpenShift AI (RHOAI), Red Hat OpenShift Dev Spaces · no fix planned: Red Hat Enterprise Linux AI (RHEL AI) 3, Red Hat OpenShift AI (RHOAI), Red Hat OpenShift Dev Spaces · updated 2026-09-16 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-92081.json)","depth":"sunlit","depthScore":33,"depthScoreParts":{"impact":32.5,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}