CVE-2026-45109

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

Published: May 11, 2026Modified: May 14, 2026

Severity

HIGH

CVSS Scores

7.5/ 10.0

CVSS_V3

High

Vector String

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

Details

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

Affected Packages

nextnpm

Version Ranges:

Version Range: 15.2.0 - 15.5.18

nextnpm

Version Ranges:

Version Range: 16.0.0 - 16.2.6

References

https://github.com/vercel/next.js/security/advisories/GHSA-267c-6grr-h53fWEB https://github.com/vercel/next.js/security/advisories/GHSA-26hh-7cqf-hhc6WEB

Aliases

CVE-2026-45109

CVE-2026-45109 - Next.js has a Middleware / Proxy bypass in App Router applications via segment-prefetch routes - Incomplete Fix Follow-Up | OSV Watch