The Forum Post That Transferred Money From Your Bank Account
In 2008, a vulnerability researcher demonstrated a CSRF attack against a major bank. He posted a message on a public forum that contained a hidden image tag. When logged-in bank customers visited that forum, their browsers automatically sent a request to the bank's transfer endpoint — silently moving money to an attacker-controlled account. The customers never clicked anything. They just read a forum post.
CSRF sits in a category of attacks that feel almost unfair: the victim does everything right. They log in securely. They never share their password. They browse normally. And they still get attacked — because their browser is being used against them.
The victim does nothing wrong
This is what makes CSRF genuinely insidious. Unlike phishing, the victim does not hand over their credentials. Unlike malware, nothing is installed. The attack uses the browser's legitimate behaviour — sending cookies automatically — against the user. The entire burden of prevention falls on the website developer, not the user.
In a CSRF attack, the victim does not click any suspicious link or enter their password. How does the attack still succeed?