Nuxt: Incomplete fix for GHSA-9v7c-q64q-vv33: a leading // in the request path bypasses server/middleware path checks and server route rules on page 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-2026-128077: 0.27% estimated exploitation activity in the next 30 days; percentile 19.57 (FIRST EPSS, 2026-11-14). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary Since `4.6.0`, Nuxt parses a request path that starts with `//` as a URL with a host before rendering a page, so `//x/admin` renders the page at `/admin`. Nitro's routing, Nitro's route rules and `server/middleware` see the path as `//x/admin`, so server-side checks keyed on `/admin` do not apply. The fix for GHSA-9v7c-q64q-vv33 in `4.6.3` covered dot segments but not this form.

Impact An unauthenticated attacker can bypass server-side controls that match on the request path of a page route. A route-scoped server handler is skipped: ```ts // nuxt.config.ts export default defineNuxtConfig({ serverHandlers: [{ route: '/admin', middleware: true, handler: '~~/server/admin-guard.ts' }], }) ``` ```ts // server/admin-guard.ts export default defineEventHandler((event) => { if (!isAuthenticated(event)) { throw createError({ statusCode: 401 }) } }) ``` With this handler, `/admin` returns 401, but…

Published by the source

13 Nov 2026, 19:32 UTC

Last modified by the source

13 Nov 2026, 19:45 UTC

Source last checked

14 Nov 2026, 07:30 UTC

1. Revision 2 · amended · 14 Nov 2026

   Amended from osv record GHSA-r99w-jh2x-3mg9

2. Revision 1 · created · 13 Nov 2026

   Published from ghsa record GHSA-r99w-jh2x-3mg9

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# Patch Next advisory brief: CVE-2026-128077

Advisory: Nuxt: Incomplete fix for GHSA-9v7c-q64q-vv33: a leading `//` in the request path bypasses `server/middleware` path checks and server route rules on page routes
IDs: CVE-2026-128077, GHSA-r99w-jh2x-3mg9
Record: https://patchnext.com/advisories/cve-2026-128077 (revision 2, source checked 14 Nov 2026, 07:30 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/nitro-server 4.6.4. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm @nuxt/nitro-server: affected >= 4.6.0, < 4.6.4; fixed in 4.6.4

## Suggested inspection (read-only)
- `npm ls @nuxt/nitro-server --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/nitro-server.
- 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-r99w-jh2x-3mg9 (GitHub-reviewed advisory GHSA-r99w-jh2x-3mg9 lists affected ranges: npm @nuxt/nitro-server >=4.6.0 <4.6.4)
- Verified: https://osv.dev/vulnerability/GHSA-r99w-jh2x-3mg9 (OSV record GHSA-r99w-jh2x-3mg9 lists affected ranges: npm @nuxt/nitro-server >=4.6.0 <4.6.4 (fixed))

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