CVE-2026-45109: Next.js has a Middleware / Proxy bypass in App Router applications via segment-prefetch routes - Incomplete Fix Follow-Up
(updated )
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
- access.redhat.com/errata/RHSA-2026:34608
- access.redhat.com/errata/RHSA-2026:37272
- access.redhat.com/errata/RHSA-2026:40974
- access.redhat.com/errata/RHSA-2026:54435
- access.redhat.com/security/cve/CVE-2026-45109
- bugzilla.redhat.com/show_bug.cgi?id=2477190
- github.com/advisories/GHSA-26hh-7cqf-hhc6
- github.com/vercel/next.js/releases/tag/v15.5.18
- github.com/vercel/next.js/releases/tag/v16.2.6
- github.com/vercel/next.js/security/advisories/GHSA-267c-6grr-h53f
- github.com/vercel/next.js/security/advisories/GHSA-26hh-7cqf-hhc6
- nvd.nist.gov/vuln/detail/CVE-2026-45109
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-45109.json
- vercel.com/changelog/next-js-may-2026-security-release
Code Behaviors & Features
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