nextjs-proxy-csp-hardening

Configuring a per-request nonce in Next.js proxy.ts involves generating a unique nonce per request, propagating it through the x-nonce header, and applying it to the response CSP to authorize script execution securely.

Migrating from middleware.ts to proxy.ts for CSP in Next.js App Router involves replacing the middleware scaffold with a proxy.ts file to enforce strict CSP and per-request nonce generation for production hardening.

Hardening a Next.js proxy requires a strict Content-Security-Policy that explicitly defines base-uri, form-action, and frame-ancestors directives alongside the per-request nonce to prevent injection and clickjacking attacks.

Yes, you can use proxy.ts to apply comprehensive security headers and enforce a strict CSP in a Next.js App Router project, providing a defendable baseline for production apps.

A per-request nonce is needed for CSP in Next.js to ensure that only explicitly authorized scripts execute on each request, preventing cross-site scripting by making injected static scripts fail the policy check.

The best way to set up frame-ancestors and form-action in Next.js CSP is to explicitly declare them within the Content-Security-Policy header applied by your proxy.ts file to prevent clickjacking and unauthorized form submissions.