Myfaces Cross-Site Request Forgery

In the default configuration, Apache MyFaces Core versions 2.2.0 to 2.2.13, 2.3.0 to 2.3.7, 2.3-next-M1 to 2.3-next-M4, and 3.0.0-RC1 use cryptographically weak implicit and explicit cross-site request forgery (CSRF) tokens. Due to that limitation, it is possible (although difficult) for an attacker to calculate a future CSRF token value and to use that value to trick a user into executing unwanted actions on an application. (2021-02-19, CVE-2021-26296)

The absence of Anti-CSRF tokens may lead to a Cross-Site Request Forgery attack that can result in executing a specific application action as another logged in user, e.g. steal their account by changing their email and password or silently adding a new admin user account when executed from the administrator account.

The attacker may copy one of your web application forms, e.g. email/password change form.

The webpage will contain a form with the exact set of fields as the original application but with input values already provided and the submit button replaced with a Javascript code causing auto-submission. When the page is accessed the form will be immediately submitted and page contents replaced with a valid content or a redirect to your original application.

One of your application users who is already logged in can be then tricked to navigate to such malicious page e.g. by clicking a link in a phishing email, and the pre-populated form content will be submitted to your application like it would be submitted by your user.