CVE-2026-47200: Nuxt Remote Code Execution Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-hg3f-28rg-4jxj",
  "modified" : "2026-07-08T17:35:13Z",
  "published" : "2026-05-29T17:15:11Z",
  "aliases" : [ "CVE-2026-47200" ],
  "summary" : "Nuxt's route middleware is not enforced when rendering `.server.vue` pages via `/__nuxt_island/page_*`",
  "details" : "### Summary\n\nWhen `experimental.componentIslands` is enabled (default in Nuxt 4), any `.server.vue` file under `pages/` is automatically registered as a server island under the key `page_<routeName>` and exposed via the `/__nuxt_island/:name` endpoint. Until this fix, requests through that endpoint rendered the page component directly via the SSR renderer without instantiating Vue Router, which meant route middleware declared on the page (including `definePageMeta({ middleware })`) did not run.\n\nFor Nuxt applications that gate a `.server.vue` *page* behind route middleware as their sole auth check, an unauthenticated attacker could bypass that check by requesting `/__nuxt_island/page_<routeName>_<anyhash>` directly and receiving the server-rendered HTML.\n\n### Affected configurations\n\nAll three conditions must hold for an application to be vulnerable:\n\n1. `experimental.componentIslands` is enabled (the default in Nuxt 4; opt-in in Nuxt 3).\n2. The application defines one or more `.server.vue` files under `pages/`, registering them as routed pages.\n3. Authentication / authorization for at least one such page is enforced solely via route middleware (`middleware/*.ts` referenced from `definePageMeta`), without a server-side check inside the page or its data layer.\n\nApplications that enforce auth inside the island's own data layer (server-only API routes, `useRequestEvent` + manual session checks, etc.) were not affected. The general \"route middleware does not run for non-page island *components*\" behaviour is documented and unchanged; this advisory concerns the `.server.vue` *page* case specifically, where running middleware is the user's clear expectation.\n\n### Details\n\n- Build (`packages/nuxt/src/components/templates.ts`): `.server.vue` pages are registered as island components with `page_` prefix, making them addressable through `/__nuxt_island/page_<routeName>_<hashId>`.\n- Runtime (`packages/nitro-server/src/runtime/handlers/island.ts`): the handler resolves the requested island component and renders it via `renderer.renderToString(ssrContext)`. The Vue Router plugin previously short-circuited middleware execution whenever `ssrContext.islandContext` was set.\n- The two paths interact so that route middleware declared on the source page never runs.\n\n### Proof of concept\n\nGiven a page `app/pages/secret.server.vue`:\n\n```vue\n<script setup lang=\"ts\">\ndefinePageMeta({ middleware: 'auth' })\n</script>\n\n<template>\n<h1>SECRET DATA</h1>\n</template>\n```\n\nwith `middleware/auth.ts` blocking unauthenticated access:\n\n```bash\n# Direct page request: blocked by middleware\ncurl -i http://localhost:3000/secret\n# -> 403 / redirect, depending on the middleware\n\n# Island request: middleware did not run before this fix\ncurl -i 'http://localhost:3000/__nuxt_island/page_secret_anyhash'\n# -> 200 OK, body includes <h1>SECRET DATA</h1>\n```\n\n### Patches\n\nPatched in `nuxt@4.4.6` and `nuxt@3.21.6` by [#35092](https://github.com/nuxt/nuxt/pull/35092). The Vue Router plugin now runs middleware and redirect handling for `page_*` islands (i.e. islands that originate from `.server.vue` files in `pages/`). The island handler propagates middleware-issued responses (`~renderResponse`), and a new `beforeResolve` guard returns HTTP 400 when the requested `page_<name>` does not match the route component the URL resolves to.\n\nNon-page island components are unaffected - they continue to render without route middleware, by design.\n\n### Workarounds\n\nIf you cannot upgrade immediately:\n\n- Enforce authentication inside the `.server.vue` page itself, not via route middleware. Read the session from `useRequestEvent()` and `throw createError({ statusCode: 401 })` (or redirect) before returning data. This is the recommended pattern for islands regardless of this advisory.\n- Disable `experimental.componentIslands` if your app does not use the feature.\n- If your app must keep route-middleware-only auth, gate the `/__nuxt_island/page_*` URL prefix at your reverse proxy or in a server middleware.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "nuxt"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "3.11.0"
      }, {
        "fixed" : "3.21.6"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 3.21.5"
    }
  }, {
    "package" : {
      "ecosystem" : "npm",
      "name" : "@nuxt/nitro-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "3.20.0"
      }, {
        "fixed" : "3.21.6"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 3.21.5"
    }
  }, {
    "package" : {
      "ecosystem" : "npm",
      "name" : "@nuxt/nitro-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "4.2.0"
      }, {
        "fixed" : "4.4.6"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 4.4.5"
    }
  }, {
    "package" : {
      "ecosystem" : "npm",
      "name" : "nuxt"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "4.0.0-alpha.1"
      }, {
        "fixed" : "4.4.6"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 4.4.5"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/nuxt/nuxt/security/advisories/GHSA-hg3f-28rg-4jxj"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-47200"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/nuxt/nuxt/issues/19772"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/nuxt/nuxt/pull/35092"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/nuxt/nuxt"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-284", "CWE-288" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-29T17:15:11Z",
    "nvd_published_at" : "2026-06-12T14:16:32Z"
  }
}