Mitigating CSRF Vulnerabilities
Cross-Site Request Forgery (CSRF) is a type of attack that tricks a user into executing unwanted actions on a web application where they are authenticated. To effectively mitigate CSRF vulnerabilities, consider the following strategies:
- Anti-CSRF Tokens: Implement anti-CSRF tokens in forms and state-changing requests. These tokens are unique to each session and action, and should be verified with each request.
- SameSite Cookies: Utilize the 'SameSite' attribute on cookies to control when cookies are sent with requests. Setting 'SameSite' to 'Strict' or 'Lax' helps prevent CSRF by restricting cookie transmission.
- Custom HTTP Headers: Require custom headers in AJAX requests. When making API calls, enforce the use of specific headers that are not sent by browsers for cross-origin requests.
- Double Submit Cookie: In this approach, send a CSRF token both as a cookie and as a request parameter. The server then verifies that both values match.
- User Interaction Confirmation: For sensitive operations, require users to confirm their actions via an additional input step, such as re-entering their password.
- Content Security Policy (CSP): Implement CSP to limit the sources from which scripts can be executed, thereby reducing the risk of exploitation.
Regularly review your application for CSRF vulnerabilities by employing security testing and code reviews. Keeping your libraries and frameworks updated is also crucial in maintaining security.