HomeTechnologyWeb DevelopmentWhat is CSRF (Cross-Site Request Forgery)?
Technology·2 min·Updated Mar 9, 2026

What is CSRF (Cross-Site Request Forgery)?

Cross-Site Request Forgery

Quick Answer

Cross-Site Request Forgery (CSRF) is a type of security vulnerability that allows an attacker to trick a user into performing actions on a web application without their consent. This can lead to unauthorized actions being taken on behalf of the user, potentially compromising their account or data.

Overview

CSRF occurs when a malicious website sends a request to a different site where a user is authenticated, using the user's credentials without their knowledge. For example, if a user is logged into their bank account and visits a harmful site, that site could send a request to transfer money from the user's account without their consent. This type of attack exploits the trust that a web application has in the user's browser, making it crucial for developers to implement security measures against it. To understand how CSRF works, consider a scenario where a user is tricked into clicking a link that performs an action on another website. The link could be disguised as something harmless, but when clicked, it sends a request to the target site, like changing the user's email address or making a purchase. The attack relies on the fact that the user's browser automatically includes their credentials, such as cookies, in the request, making it seem legitimate to the web application. Preventing CSRF is important in web development because it protects users from unauthorized actions that could lead to data loss or financial theft. Developers can use techniques like anti-CSRF tokens, which are unique to each session and must be included in requests that modify data. By understanding and addressing CSRF vulnerabilities, developers can create safer web applications that better protect user information.


Frequently Asked Questions

You might not be able to tell just by looking at a website, but common signs include the lack of anti-CSRF tokens in forms or actions that change user data. Security testing tools can help identify vulnerabilities.
A successful CSRF attack can lead to unauthorized actions taken on behalf of the user, such as transferring funds, changing passwords, or even deleting accounts. This can result in financial loss or data breaches for users.
Developers can implement anti-CSRF tokens, validate the origin of requests, and ensure that state-changing actions require additional verification. These measures help ensure that requests are made intentionally by the user.