CSRF Protection
CSRF protection defends against cross-site request forgery, where a malicious site tricks a victim browser into sending authenticated requests to your API using existing cookies or sessions. Defenses include unpredictable anti-CSRF tokens, SameSite cookie attributes, and verifying Origin or Referer headers on state-changing calls.
Technical Architecture & Deep-Dive
Classic CSRF targets cookie-based sessions. A user stays logged into your app, visits a malicious site, and that site auto-submits a form or fetch to your API. Because the browser attaches session cookies automatically, the API may treat the call as legitimate.
Bearer-token APIs are less vulnerable to classic CSRF but still need origin checks when tokens live in browser storage. Edge gateways can require custom headers, validate origins, and reject cross-site POSTs before they reach upstream services.
Key Architectural Benefits
Implement CSRF Protection at the Edge
Deploy lightweight API aggregation, edge caching, and secret injection in minutes without Docker containers or complex servers.
Frequently Asked Questions
Q:Are APIs using Authorization bearer headers immune to CSRF?
Mostly, because browsers do not attach bearer headers cross-site unless attacker script runs on your origin. Still validate origins on sensitive browser-initiated writes for defense in depth.
Related Architecture Concepts
Cross-Origin Resource Sharing (CORS) is a browser security mechanism that controls whether a web page on one origin may read responses from another origin. Servers advertise permitted caller origins and methods using HTTP response headers such as Access-Control-Allow-Origin.
Allowed origins are a configured list of website domains permitted to call an API from a browser. The server or gateway checks the Origin header of each request and only returns CORS permission headers, or accepts the request, when the origin is on the allowlist.
HMAC authentication uses a hash-based message authentication code, computed from a message and a shared secret key, to prove that a request came from a holder of the secret and was not modified. The receiver recomputes the HMAC and compares it to the value sent.
Webhook signature verification is validating that an incoming webhook was sent by the expected provider and was not altered. Providers sign each payload with a shared secret, typically using HMAC-SHA256, and your endpoint recomputes the signature and compares it before trusting the event.
Ready-to-Use Edge Recipes
To solve call clerk backend api from client side, never execute unauthenticated requests or embed private tokens directly in client bundles. RealComposer acts as a sub-10ms edge gateway running on Cloudflare Workers that securely injects credentials from your Secret Vault, normalizes responses, and prevents unauthorized API usage. Route calls through your RealComposer edge URL to guarantee complete privacy, robust origin validation, and low mobile latency.
To solve reverse proxy for third party api key protection, never execute unauthenticated requests or embed private tokens directly in client bundles. RealComposer acts as a sub-10ms edge gateway running on Cloudflare Workers that securely injects credentials from your Secret Vault, normalizes responses, and prevents unauthorized API usage. Route calls through your RealComposer edge URL to guarantee complete privacy, robust origin validation, and low mobile latency.
Webflow is a purely static and frontend visual builder with no backend server. To call private APIs from Webflow custom code without revealing secrets in the browser inspector, route requests through RealComposer. RealComposer stores your API keys in an AES-256-GCM vault, injects credentials at the edge, and handles CORS headers automatically.