The video tutorial explains how to mitigate cross-site request forgery (CSRF) attacks using synchronizer tokens. It covers the generation and validation of secure random tokens on the server, which are sent with every client request to ensure the request's authenticity. The tutorial provides an example of a secure signup form that uses these tokens to prevent unauthorized actions. It emphasizes the importance of session-based tokens and demonstrates how to generate and validate them using PHP. The tutorial also highlights the need for secure signups and trusted sources.

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