CVE-2026-114131: Nuxt: Route rules are matched against the raw request path, so a percent-encoded segment can bypass `appMiddleware` on dynamic and catch-all routes
Nuxt is an open-source web development framework for Vue.js. From 3.11.0 until 3.21.4 and 4.4.4, Nuxt compares route-rule keys with the raw request path while route resolution decodes dynamic and catch-all parameters, allowing a percent-encoded segment to resolve to a protected page without matching the routeRules entry intended for that path. As a result, appMiddleware can be skipped during server rendering and an unauthenticated requester can receive the gated page and its SSR data. The same mismatch affects app-manifest rules including redirect, appLayout, ssr, prerender, and payload flags derived from cache, isr, and swr. This vulnerability is fixed in 4.4.4 and 3.21.4.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Nuxtto a version that resolves this vulnerability.Fixed in 4.4.4 - Upgrade
Upgrade
Nuxtto a version that resolves this vulnerability.Fixed in 3.21.4
Event History
Frequently Asked Questions
Which deployments are exposed?
Nuxt versions from 3.11.0 through versions before 3.21.4, and Nuxt 4 versions before 4.4.4, are affected. Exposure requires routeRules intended to protect dynamic or catch-all routes with appMiddleware.
What does an attacker need to exploit this issue?
An unauthenticated remote requester can use a percent-encoded path segment that resolves to a protected dynamic or catch-all route. No privileges or user interaction are required.
What can be exposed or altered by the route-rule mismatch?
appMiddleware can be skipped during server-side rendering, allowing access to a gated page and its SSR data. Redirect, appLayout, ssr, prerender, payload, cache, isr, and swr-related app-manifest behavior can also be affected.
What version should be deployed to remediate the issue?
Upgrade Nuxt 3 to 3.21.4 or later, or Nuxt 4 to 4.4.4 or later.