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

HIGH 7.5CVE-2026-45109 · GHSA-26hh-7cqf-hhc6 · Published 13/05/2026 · updated 26/10/2026

Package	Affected versions	Patched versions
next.js vercel	`≥ 15.2.0, < 15.5.18≥ 16.0.0, < 16.2.6`	`15.5.1816.2.6`
next npm	`≥ 15.2.0, < 15.5.18≥ 16.0.0, < 16.2.6`	`15.5.1816.2.6`

Description

Impact

It was found that the fix addressing CVE-2026-44575 did not apply to middleware.ts with Turbopack. Refer to CVE-2026-44575 for further details.

References

CVE CVE-2026-44575

NVD description

Next.js is a React framework for building full-stack web applications. From 15.2.0 to before 15.5.18 and 16.2.6, it was found that the fix addressing CVE-2026-44575 did not apply to middleware.ts with Turbopack. This vulnerability is fixed in 15.5.18 and 16.2.6.

References

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