Typo3 Cross-Site Request Forgery

TYPO3 is an open source PHP based web content management system released under the GNU GPL. It has been discovered that the new TYPO3 v11 feature that allows users to create and share deep links in the backend user interface is vulnerable to cross-site-request-forgery. The impact is the same as described in TYPO3-CORE-SA-2020-006 (CVE-2020-11069). However, it is not limited to the same site context and does not require the attacker to be authenticated. In a worst case scenario, the attacker could create a new admin user account to compromise the system. To successfully carry out an attack, an attacker must trick his victim to access a compromised system. The victim must have an active session in the TYPO3 backend at that time. The following Same-Site cookie settings in $GLOBALS[TYPO3_CONF_VARS][BE][cookieSameSite] are required for an attack to be successful: SameSite=strict: malicious evil.example.org invoking TYPO3 application at good.example.org and SameSite=lax or none: malicious evil.com invoking TYPO3 application at example.org. Update your instance to TYPO3 version 11.5.0 which addresses the problem described. (2021-10-05, CVE-2021-41113)

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.