CVE-2026-44574 — Next.js: Middleware / Proxy bypass through dynamic route parameter injection
Next.js is a React framework for building full-stack web applications. From 15.4.0 to before 15.5.16 and 16.2.5, applications that rely on middleware to protect dynamic routes c…
Published: 2026-05-13 · CVSS: 8.1 · CVSS 3.1
Next.js is a React framework for building full-stack web applications. From 15.4.0 to before 15.5.16 and 16.2.5, applications that rely on middleware to protect dynamic routes can be vulnerable to authorization bypass. In affected deployments, specially crafted query parameters can alter the dynamic route value seen by the page while leaving the visible path unchanged, which can allow protected content to be rendered without passing the expected middleware check. This vulnerability is fixed in 15.5.16 and 16.2.5.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7