Next.js Data Protection Unauthorized Access

The vulnerability of the Next.js web application development software platform is related to the transfer of the x-middleware-subrequest-id parameter to external hosts. Exploiting this vulnerability could allow an attacker operating remotely to gain unauthorized access to protected information...

CVE-2025-30218

Next.js is a React framework for building full-stack web applications. To mitigate CVE-2025-29927, Next.js validated the x-middleware-subrequest-id which persisted across multiple incoming requests. However, this subrequest ID is sent to all requests, even if the destination is not the same host ...