Cross-Site Request Forgery (CSRF) remains a critical web security vulnerability, and double-token verification is a widely adopted defense mechanism. This article breaks down the CSRF attack chain and provides a step-by-step implementation of double-token verification in frontend engineering. Key considerations include token generation, storage, and validation across client and server. While the approach is well-known, the article offers a clear, code-driven explanation suitable for production systems. Developers should also consider additional layers like SameSite cookies and CORS policies. This content is valuable for teams hardening their web applications against CSRF attacks.
A practical guide to CSRF attack chains and double-token verification for frontend security, with engineering trade-offs.