High· 7.5GHSA-26hh-7cqf-hhc6 CVE-2026-45109CWE-288Published May 11, 2026

Next.js has a Middleware / Proxy bypass in App Router applications via segment-prefetch routes - Incomplete Fix Follow-Up

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Affected versions

15.2.0 → fixed in 15.5.1816.0.0 → fixed in 16.2.6

Details

### Impact It was found that the fix addressing [CVE-2026-44575](https://github.com/vercel/next.js/security/advisories/GHSA-267c-6grr-h53f) did not apply to `middleware.ts` with Turbopack. Refer to [CVE-2026-44575](https://github.com/vercel/next.js/security/advisories/GHSA-267c-6grr-h53f) for further details. ### References - [CVE CVE-2026-44575](https://github.com/vercel/next.js/security/advisories/GHSA-267c-6grr-h53f)

The fix

No fix commit could be resolved for this advisory (it may reference an issue tracker or a non-GitHub patch). See the references below.