{"id":"CVE-2026-44582","aliases":["GHSA-vfv6-92ff-j949"],"url":"https://o3.security/vulnerability/CVE-2026-44582","summary":"Next.js: Cache poisoning via collisions in React Server Component cache-busting","details":"### Impact\n\nReact Server Component responses can be vulnerable to cache poisoning in deployments that rely on shared caches with insufficient response partitioning. In affected conditions, collisions in the `_rsc` cache-busting value can allow an attacker to poison cache entries so users receive the wrong response variant for a given URL.\n\n### Fix\n\nWe strengthened the `_rsc` cache-busting mechanism to make practical collisions significantly harder and to better separate response variants that should not share cache entries.\n\n### Workarounds\n\nIf you cannot upgrade immediately, ensure intermediary caches correctly honor `Vary` for RSC-related request headers, or disable shared caching for affected RSC responses until you can deploy a patched release.","published":"2026-05-13T17:08:22.240Z","modified":"2026-08-12T03:51:09.983953161Z","cvss":{"score":3.7,"severity":"LOW","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N"},"epss":{"score":0.00215,"percentile":0.12025,"asOf":"2026-08-14"},"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-2026-44582.json"},{"type":"ADVISORY","url":"https://github.com/vercel/next.js/security/advisories/GHSA-vfv6-92ff-j949"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-44582"},{"type":"PACKAGE","url":"https://github.com/vercel/next.js"},{"type":"WEB","url":"https://github.com/vercel/next.js/releases/tag/v15.5.16"},{"type":"WEB","url":"https://github.com/vercel/next.js/releases/tag/v16.2.5"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:09.983953161Z"}}