CVE-2026-44575 — Next.js: Middleware / Proxy bypass in App Router applications via segment-prefetch routes
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 c…
Published: 2026-05-13 · CVSS: 7.5 · CVSS 3.1
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7