# CVE-2026-44575: Next.js: Middleware / Proxy bypass in App Router applications via segment-prefetch routes

> CVE-2026-44575: Next.js: Middleware / Proxy bypass in App Router applications via segment-prefetch routes. CVSS 7.5 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-44575
Last updated: 2026-08-13T13:19:03Z

- Published: 2026-05-13 16:54 UTC · Updated: 2026-08-13 13:19 UTC · Assigner: GitHub\_M
- CVSS: 7.5 (CVSS 3.1) · Severity: High · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- EPSS: 1.6%, 76th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-288

## Description

Next.js is a React framework for building full-stack web applications. From 15.2.0 to before 15.5.16 and 16.2.5, App Router applications that rely on middleware or proxy-based checks for authorization can allow unauthorized access through transport-specific route variants used for segment prefetching. In affected configurations, specially crafted .rsc and segment-prefetch URLs can resolve to the same page without being matched by the intended middleware rule, which can allow protected content to be reached without the expected authorization check. This vulnerability is fixed in 15.5.16 and 16.2.5.

## Affected vendors and products

- Red Hat: Red Hat Enterprise Linux 10
- Red Hat: Red Hat Enterprise Linux 7
- Red Hat: Red Hat Enterprise Linux 8
- Red Hat: Red Hat Enterprise Linux 9
- Red Hat: Red Hat Enterprise Linux AI (RHEL AI) 3
- Red Hat: Red Hat Trusted Artifact Signer 1.3
- Red Hat: Red Hat Trusted Artifact Signer 1.4
- Red Hat: Streams for Apache Kafka 2.9.4
- Red Hat: streams for Apache Kafka 3
- vercel: next.js

## Tracked companies

- [Vercel](https://rewindex.com/company/vercel.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-44575)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-44575)
- [https://github.com/vercel/next.js/security/advisories/GHSA-267c-6grr-h53f](https://github.com/vercel/next.js/security/advisories/GHSA-267c-6grr-h53f)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-44575 · Markdown: https://rewindex.com/cve/CVE-2026-44575.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-44575 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:01:56.536Z