Nuxt: Route rules are matched against the raw request path, so a percent-encoded segment can bypass appMiddleware on dynamic and catch-all routes

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

6.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

EPSS

• CVE-2026-114131: 0.36% estimated exploitation activity in the next 30 days; percentile 30.19 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary Nuxt compared routeRules keys against the raw request path, without decoding percent-encoding, while the router decodes parameters when it resolves a route. A request whose path is percent-encoded can therefore resolve to a page while failing to match the route rule meant to protect it, so the rule's appMiddleware never runs, including during server rendering. Impact For a page served through a dynamic or catch-all route, an attacker can percent-encode a character in the path to skip the rule: Requesting /users/%61dmin still renders app/pages/users/[id].vue with id decoded to admin, but the rule keyed /users/admin does not match, so auth does not run and the server renders and returns the gated page to an unauthenticated visitor. No privileges and no user interaction are required, and only ASCII characters are involved. Purely static ASCII routes are not affected: static segments are matched without decoding, so a request for /%61dmin does not resolve to the page registered…

Published by the source

22 Oct 2026, 16:50 UTC

Last modified by the source

22 Oct 2026, 17:00 UTC

Source last checked

26 Oct 2026, 13:07 UTC

1. Revision 4 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-6gq8-jgmh-3ffp

2. Revision 3 · amended · 24 Oct 2026

   Amended from osv record GHSA-6gq8-jgmh-3ffp

3. Revision 2 · amended · 23 Oct 2026

   Amended from ghsa record GHSA-6gq8-jgmh-3ffp

4. Revision 1 · created · 23 Oct 2026

   Published from ghsa record GHSA-6gq8-jgmh-3ffp

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# Patch Next advisory brief: CVE-2026-114131

Advisory: Nuxt: Route rules are matched against the raw request path, so a percent-encoded segment can bypass `appMiddleware` on dynamic and catch-all routes
IDs: CVE-2026-114131, GHSA-6gq8-jgmh-3ffp
Record: https://patchnext.com/advisories/cve-2026-114131 (revision 4, source checked 26 Oct 2026, 13:07 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: nuxt 4.4.4, 3.21.4. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm nuxt: affected >= 4.0.0, < 4.4.4; >= 3.11.0, < 3.21.4; fixed in 4.4.4, 3.21.4

## Suggested inspection (read-only)
- `npm ls nuxt --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on nuxt.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-6gq8-jgmh-3ffp (GitHub-reviewed advisory GHSA-6gq8-jgmh-3ffp lists affected ranges: npm nuxt >=4.0.0 =3.11.0 <3.21.4)
- Verified: https://osv.dev/vulnerability/GHSA-6gq8-jgmh-3ffp (OSV record GHSA-6gq8-jgmh-3ffp lists affected ranges: npm nuxt >=4.0.0 =3.11.0 <3.21.4 (fixed))

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