{"id":"CVE-2026-71315","aliases":["GHSA-hxvh-4h3w-prp9"],"url":"https://o3.security/vulnerability/CVE-2026-71315","summary":"Nuxt route rules silently dropped for mixed-case paths, bypassing appMiddleware auth gates (incomplete fix for CVE-2026-53721)","details":"### Impact\n\nNuxt matches route rules case-insensitively by default (mirroring vue-router's default `sensitive: false` routing). The fix for GHSA-mm7m-92g8-7m47 / CVE-2026-53721 lowercased the *lookup* path before matching route rules, but the route-rule *keys* compiled into the matcher were left verbatim. As a result, any route rule whose key contains an uppercase character (for example `/Admin`, `/Dashboard/**`, or the rules Nuxt derives from PascalCase/camelCase page files such as `pages/Admin.vue`) never matches, because every lookup is folded to lowercase while the key stays mixed-case.\n\nvue-router still serves the page case-insensitively, so the page renders with none of its Nuxt route-rule protections applied. The most serious consequence is an authorization bypass: an `appMiddleware` rule used as an auth gate (`routeRules: { '/Admin/dashboard': { appMiddleware: 'auth' } }`) is dropped, and `/Admin/dashboard`, `/admin/dashboard`, and `/ADMIN/dashboard` all render the protected page (and its SSR-fetched data) to an unauthenticated visitor instead of redirecting to login. The same gap drops Nuxt's other app-side route-rule behaviours for mixed-case keys, including the client redirect middleware, the app-side `ssr: false` decision, `prerender`, and payload handling.\n\n### Patches\n\nFixed in `nuxt@4.5.1` (4.x) and `nuxt@3.21.10` (3.x). The route-rule matcher now case-folds the compiled keys the same way it folds the lookup path, so key and lookup normalisation are symmetric. Both sides are gated on `router.options.sensitive`: with `sensitive: true` (case-sensitive routing) configured casing is preserved on both sides.\n\nScope note: server-emitted per-route `headers`, server `redirect`, and `proxy` are matched by Nitro's own case-sensitive route-rule matcher, not by Nuxt's app-level matcher. They are unchanged by this advisory. The fix covers the app-level protections Nuxt owns (`appMiddleware`, `appLayout`, the client redirect middleware, the app `ssr` decision, `prerender`, and payload).\n\n### Workarounds\n\nIf you cannot upgrade immediately, any one of:\n\n- Key all `routeRules` (and name your page files) in lowercase, so the keys already match the folded lookup path.\n- Set `router: { options: { sensitive: true } }` so routing and route-rule matching are both case-sensitive and exact (requests must then use the exact casing).\n- Enforce the sensitive protections server-side independently of route rules (for example a server middleware that checks auth), which does not rely on case-insensitive route-rule matching.","published":"2026-08-05T21:05:15.379Z","modified":"2026-10-28T02:30:47.945286695Z","cvss":{"score":8.2,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N"},"epss":{"score":0.00267,"percentile":0.19029,"asOf":"2026-09-17"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"nuxt","fixedVersion":"4.5.1"},{"ecosystem":"npm","name":"nuxt","fixedVersion":"3.21.10"}],"fix":{"url":"https://github.com/nuxt/nuxt/commit/619963309e082190bac4a26b05f2dd155b039b81","label":"nuxt/nuxt@6199633"},"references":[{"type":"WEB","url":"https://github.com/nuxt/nuxt/releases/tag/v3.21.10"},{"type":"WEB","url":"https://github.com/nuxt/nuxt/releases/tag/v4.5.1"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/71xxx/CVE-2026-71315.json"},{"type":"ADVISORY","url":"https://github.com/nuxt/nuxt/security/advisories/GHSA-hxvh-4h3w-prp9"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-71315"},{"type":"FIX","url":"https://github.com/nuxt/nuxt/commit/619963309e082190bac4a26b05f2dd155b039b81"},{"type":"FIX","url":"https://github.com/nuxt/nuxt/commit/ad624a75ad2d215f43633f6b40be346a7194d34d"},{"type":"PACKAGE","url":"https://github.com/nuxt/nuxt"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-28T02:30:47.945286695Z"}}