{"id":"GHSA-4633-3j49-mh5q","revision":"002750499b39434d83a6e0e2939942fa","records":[{"revision":"002750499b39434d83a6e0e2939942fa","observedAt":"2026-10-24T13:17:17.793+00:00","statement":{"source":"osv","id":"GHSA-4633-3j49-mh5q","aliases":["CVE-2026-64647"],"title":"Next.js: Cache confusion of response bodies for requests with bodies containing invalid UTF-8 byte sequences","description":"## Impact\n\nA server-side `fetch` with a request body may return a cached **response** body from a different request to the same URL but different body. Confidential data in the `POST`'s **response** body would then leak to unauthorized requests. Though the request itself will not be deduped.\n\nThis is only an issue when receiving request bodies with a content type charset other than UTF-8. For example, the UTF-16 byte sequences for `삃삃` and `섄섄` in the request body would share the same cache.\n\n## Workarounds\n\nIf you cannot upgrade, consider only making fetch requests with UTF-8 bodies (default in Next.js). Applications using Pages Router are not vulnerable.","state":0,"publishedAt":"2026-07-22T23:06:12+00:00","modifiedAt":"2026-09-10T03:50:51.3901572+00:00","affected":[{"ecosystem":"npm","name":"next","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"13.0.0"},{"kind":"fixed","version":"15.5.21"}]}],"versions":[],"rawVersionEvidence":null},{"ecosystem":"npm","name":"next","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"16.0.0"},{"kind":"fixed","version":"16.2.11"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[{"system":"CVSS_V4","vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","score":null,"severity":null},{"system":"Publisher rating","vector":null,"score":null,"severity":"MODERATE"}],"references":["https://github.com/vercel/next.js/security/advisories/GHSA-4633-3j49-mh5q","https://github.com/vercel/next.js/pull/96008","https://github.com/vercel/next.js/commit/025bf4a5f7b47fb7758c4ebf1c931a61c451c082","https://github.com/vercel/next.js","https://github.com/vercel/next.js/releases/tag/v15.5.21","https://github.com/vercel/next.js/releases/tag/v16.2.11"],"sourceUrl":"https://github.com/advisories/GHSA-4633-3j49-mh5q","license":"GitHub Advisory Database · CC-BY-4.0","key":"osv:GHSA-4633-3j49-mh5q","identifiers":["GHSA-4633-3j49-mh5q","CVE-2026-64647"]},"retained":false,"historicalAffected":[]}],"coverage":[]}