{"id":"CVE-2026-44572","aliases":["GHSA-3g8h-86w9-wvmq"],"url":"https://o3.security/vulnerability/CVE-2026-44572","summary":"Next.js: Middleware / Proxy redirects can be cache-poisoned","details":"Next.js is a React framework for building full-stack web applications. From 12.2.0 to before 15.5.16 and 16.2.5, an external client could send a x-nextjs-data header on a normal request to a path handled by middleware that returns a redirect. When that happened, the middleware/proxy could treat the request as a data request and replace the standard Location redirect header with the internal x-nextjs-redirect header. Browsers do not follow x-nextjs-redirect, so the response became an unusable redirect for normal clients. If the application was deployed behind a CDN or reverse proxy that caches 3xx responses without varying on this header, a single attacker request could poison the cached redirect response for the affected path. Subsequent visitors could then receive a cached redirect response without a Location header, causing a denial of service for that redirect path until the cache entry expired or was purged. This vulnerability is fixed in 15.5.16 and 16.2.5.","published":"2026-05-13T15:57:15.750Z","modified":"2026-07-15T01:49:12.810067494Z","cvss":{"score":3.7,"severity":"LOW","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"next","fixedVersion":"15.5.16"},{"ecosystem":"npm","name":"next","fixedVersion":"16.2.5"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/44xxx/CVE-2026-44572.json"},{"type":"ADVISORY","url":"https://github.com/vercel/next.js/security/advisories/GHSA-3g8h-86w9-wvmq"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-44572"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-07-15T01:49:12.810067494Z"}}