CVE-2026-45109
Next.js: Middleware / Proxy bypass in App Router applications via segment-prefetch routes
CVSS Score
7.5
EPSS Score
0.5%
EPSS Percentile
42th
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.
| CWE | CWE-288 |
| Vendor | vercel |
| Product | next.js |
| Published | May 13, 2026 |
| Last Updated | Jul 16, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None
Affected Versions
vercel / next.js
>= 15.2.0, < 15.5.17 >= 16.0.0, < 16.2.6
References
github.com: https://github.com/vercel/next.js/security/advisories/GHSA-26hh-7cqf-hhc6 access.redhat.com: https://access.redhat.com/security/cve/CVE-2026-45109 bugzilla.redhat.com: https://bugzilla.redhat.com/show_bug.cgi?id=2477190 security.access.redhat.com: https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-45109.json access.redhat.com: https://access.redhat.com/errata/RHSA-2026:40974 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:37272 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:34608