{"id":"GHSA-h27x-g6w4-24gq","summary":"Next.js: Unbounded postponed resume buffering can lead to DoS","details":"## Summary\nA request containing the `next-resume: 1` header (corresponding with a PPR resume request) would buffer request bodies without consistently enforcing `maxPostponedStateSize` in certain setups. The previous mitigation protected minimal-mode deployments, but equivalent non-minimal deployments remained vulnerable to the same unbounded postponed resume-body buffering behavior.\n\n## Impact\nIn applications using the App Router with Partial Prerendering capability enabled (via `experimental.ppr` or `cacheComponents`), an attacker could send oversized `next-resume` POST payloads that were buffered without consistent size enforcement in non-minimal deployments, causing excessive memory usage and potential denial of service.\n\n## Patches\nFixed by enforcing size limits across all postponed-body buffering paths and erroring when limits are exceeded.  \n\n## Workarounds\nIf upgrade is not immediately possible:\n- Block requests containing the `next-resume` header, as this is never valid to be sent from an untrusted client.","aliases":["CVE-2026-27979"],"modified":"2026-03-19T18:47:43.991556Z","published":"2026-03-17T16:16:49Z","database_specific":{"severity":"MODERATE","github_reviewed":true,"github_reviewed_at":"2026-03-17T16:16:49Z","nvd_published_at":"2026-03-18T01:16:04Z","cwe_ids":["CWE-770"]},"references":[{"type":"WEB","url":"https://github.com/vercel/next.js/security/advisories/GHSA-h27x-g6w4-24gq"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-27979"},{"type":"WEB","url":"https://github.com/vercel/next.js/commit/c885d4825f800dd1e49ead37274dcd08cdd6f3f1"},{"type":"PACKAGE","url":"https://github.com/vercel/next.js"},{"type":"WEB","url":"https://github.com/vercel/next.js/releases/tag/v16.1.7"}],"affected":[{"package":{"name":"next","ecosystem":"npm","purl":"pkg:npm/next"},"ranges":[{"type":"SEMVER","events":[{"introduced":"16.0.1"},{"fixed":"16.1.7"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-h27x-g6w4-24gq/GHSA-h27x-g6w4-24gq.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N"}]}