Improper Handling of Case Sensitivity Affecting nuxt package, versions >=3.11.0 <3.21.7>=4.0.0-alpha.1 <4.4.7
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
Do your applications use this vulnerable package?
In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.
Test your applications- Snyk IDSNYK-JS-NUXT-17337027
- published14 Jun 2026
- disclosed12 Jun 2026
- creditAnthropic
Introduced: 12 Jun 2026
NewCVE-2026-53721 (opens in a new tab)How to fix?
Upgrade nuxt to version 3.21.7, 4.4.7 or higher.
Overview
Affected versions of this package are vulnerable to Improper Handling of Case Sensitivity through the getRouteRules function in the route rules matcher. An attacker can evade prerender, SSR, or redirect rules by sending a request with a path that uses different letter casing from the configured route rule. This causes the application to serve content without applying the intended route-specific restrictions, potentially exposing pages that should be redirected or rendered differently.
Notes
routeRuleslookups are used from both the page-router plugin and the no-pages router plugin, so the mismatch can affect SSR and client-side navigations alike, rather than only one rendering path.- The bypass is limited to deployments that rely on
routeRules.appMiddlewarefor access control; page-level middleware declared withdefinePageMeta({ middleware })is bound to the matched route record and is not part of this issue.
Workarounds
- Set
router.options.sensitive = trueso vue-router matches paths case-sensitively, preventing attackers from bypassing route rules by changing the case of a protected URL.