CVE-2026-47200: Nuxt: Route middleware not enforced when rendering `.server.vue` pages via `/__nuxt_island/page_*`

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-06-12 · updated 2026-06-17
Weakness: CWE-284

Description

Nuxt is an open-source web development framework for Vue.js. In Nuxt versions 3.11.0 to before 3.21.6 and 4.0.0-alpha.1 to before 4.4.6 and @nuxt/nitro-server versions 3.20.0 to before 3.21.6 and 4.0.0-alpha.1 to before 4.4.6, when 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. This issue has been patched in versions 3.21.6 and 4.4.6.

Affected products

nuxt: from 3.11.0 before 3.21.6; from 4.0.0 before 4.4.6 — fixed in 3.21.6, 4.4.6
Nuxt/Nitro-Server: from 3.20.0 before 3.21.6; from 4.2.0 before 4.4.6 — fixed in 3.21.6, 4.4.6

How to fix

Upgrade to a fixed version: nuxt 3.21.6, 4.4.6; Nuxt/Nitro-Server 3.21.6, 4.4.6. Check the vendor advisory for mitigations.

References

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