{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-120215 in the wild and no public exploit code.","exposure":"","fix":"No fix has been published for CVE-2026-120215 yet. Limit exposure of the affected software until one is available.","what":"CVE-2026-120215 is a low-severity vulnerability in @fastify/cors, published on 2 Nov 2026."},"fix_prompt":"Check this codebase for CVE-2026-120215 and fix it if it is affected.\n\nWhat it is: CVE-2026-120215 is a low-severity vulnerability in @fastify/cors, published on 2 Nov 2026. \nExploitation: There is no known exploitation of CVE-2026-120215 in the wild and no public exploit code.\n\nAffected product: @fastify/cors. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-120215/ (Markdown: https://insights.sbomify.com/CVE-2026-120215/index.md)","id":"CVE-2026-120215","markdown":"https://insights.sbomify.com/CVE-2026-120215/index.md","name":"CVE-2026-120215","record":{"aliases":["GHSA-8c3j-mm64-257c"],"analysis":null,"analysis_generated_by":null,"assigner":"openjs","cpe":[],"cvss":{"score":3.7,"severity":"low","source":"cna","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","version":"3.1"},"cwes":[{"id":"CWE-248","name":"Uncaught Exception"}],"description":"@fastify/cors is the CORS plugin for the Fastify web framework. In versions 8.2.0 through 11.3.x, an application that registers the plugin with the non-default onSend hook option crashes on a CORS preflight. On an OPTIONS request that carries the Origin and Access-Control-Request-Method headers, the plugin calls reply.send from inside the onSend hook and re-enters the send pipeline, so a second write of the response headers throws an uncaught ERR_HTTP_HEADERS_SENT that can terminate the Node.js process when no process-level handler is installed. An unauthenticated remote client can trigger this with a single preflight request, so the impact is availability only, and exploitation requires the non-default onSend configuration. The issue is fixed in @fastify/cors 11.4.0, where onSend is no longer an accepted hook value and registration fails with a clear error instead of crashing at request time, and users should upgrade to 11.4.0 or later. As a workaround, use any other hook such as the default onRequest, or set preflight to false.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":false,"headline":"@fastify/cors vulnerable to Denial of Service on a CORS preflight with the onSend hook","id":"CVE-2026-120215","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":null,"year":"2026"},"n_packages":0,"n_references":2,"next":{"headline":"fastify vulnerable to Denial of Service via uncaught exception on handlerTimeout with streaming responses","id":"CVE-2026-120216"},"nickname":null,"packages":[],"prev":{"headline":"@fastify/http-proxy vulnerable to prefix escape via percent-encoded backslash dot-segments","id":"CVE-2026-120214"},"products":["@fastify/cors"],"published":"2026-11-02","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-11-02","vendors":["@fastify/cors"]},"summary":null,"url":"https://insights.sbomify.com/CVE-2026-120215/"}