CVE-2026-64645

Description

Next.js is a React framework for building full-stack web applications. In versions 12.0.0 through 15.5.20 and 16.0.0 through 16.2.10, a rewrites() or redirects() rule that builds its external destination hostname from request-controlled input can be pointed at an arbitrary hostname, regardless of the rule's hostname suffix. For a rewrite, Next.js proxies the request to that arbitrary host and serves the response from the application's origin, leading to Server-Side Request forgery. A redirects() rule configured this way is vulnerable to an Open Redirect. This issue has been fixed in versions 15.5.21 and 16.2.11.

References

• https://github.com/vercel/next.js/commit/35f501357e9b0fe7c950b0d6aa8fcf5343f707e9
• https://github.com/vercel/next.js/commit/d3033266c6dff23f7be71e19341fe3a8c6e2c599
• https://github.com/vercel/next.js/releases/tag/v15.5.21
• https://github.com/vercel/next.js/releases/tag/v16.2.11
• https://github.com/vercel/next.js/security/advisories/GHSA-p9j2-gv94-2wf4