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CSRF tokens should not be transmitted using cookies. The CSRF token can be added through hidden fields, headers, and can be used with forms, and AJAX calls. Make sure that the token is not leaked in the server logs, or in the URL.
How does a CSRF attack work in OWASP?
From OWASP page : A CSRF attack works because browser requests automatically include all cookies including session cookies. To prevent it, we can use double-submit cookie hash. In some sample codes I found, basically this algorithm is found.
What is the SameSite attribute in CSRF protection?
SameSite is a cookie attribute (similar to HTTPOnly, Secure etc.) which aims to mitigate CSRF attacks. It is defined in RFC6265bis. This attribute helps the browser decide whether to send cookies along with cross-site requests.
How does cross-site request forgery ( CSRF ) attack work?
Cross-Site Request Forgery (CSRF) is a type of attack that occurs when a malicious web site, email, blog, instant message, or program causes a user’s web browser to perform an unwanted action on a trusted site when the user is authenticated. A CSRF attack works because browser requests automatically include all cookies including session cookies.
How to protect your server from CSRF attacks?
The defense against a CSRF attack is to use a CSRF token. This is a token generated by your server and provided to the client in some way. However, the big difference between a CSRF token and a session cookie is that the client will need to put the CSRF token in a non-cookie header (e.g., XSRF-TOKEN) whenever making a POST request to your backend.
How to prevent cross-site request forgery ( CSRF ) attacks?
Anti-Forgery Tokens. The client requests an HTML page that contains a form. The server includes two tokens in the response. One token is sent as a cookie. The other is placed in a hidden form field. The tokens are generated randomly so that an adversary cannot guess the values.
How are Cookie tokens generated in ASP.NET MVC?
One token is sent as a cookie. The other is placed in a hidden form field. The tokens are generated randomly so that an adversary cannot guess the values. When the client submits the form, it must send both tokens back to the server.
Which is the best framework for CSRF protection?
It is strongly recommended to research if the framework you are using has an option to achieve CSRF protection by default before trying to build your custom token generating system. For example, .NET has built-in protection that adds a token to CSRF vulnerable resources.
When to use CSRF in a REST API?
CSRF is for forms mostly and it is not used for REST APIs at all. When REST API is implemented with API keys and nonce, you could say that these 2 act as your cross-site request forgery protection. Also, when designing REST API it’s usually best to avoid such things as cookies at all.
How to include a CSRF token in an Ajax request?
To include the token in every request, start by including the following Razor code just before the tag: This will generate a hidden element with a CSRF token looking like this: To send the generated token with every AJAX request, include the following code:
Can a CSRF attack be prevented by SSL?
Moreover, using SSL does not prevent a CSRF attack, because the malicious site can send an “https://” request. Typically, CSRF attacks are possible against web sites that use cookies for authentication, because browsers send all relevant cookies to the destination web site. However, CSRF attacks are not limited to exploiting cookies.