CVE-2020-11069

/// Technical description

In TYPO3 CMS 9.0.0 through 9.5.16 and 10.0.0 through 10.4.1, it has been discovered that the backend user interface and install tool are vulnerable to a same-site request forgery. A backend user can be tricked into interacting with a malicious resource an attacker previously managed to upload to the web server. Scripts are then executed with the privileges of the victims' user session. In a worst-case scenario, new admin users can be created which can directly be used by an attacker. The vulnerability is basically a cross-site request forgery (CSRF) triggered by a cross-site scripting vulnerability (XSS) - but happens on the same target host - thus, it's actually a same-site request forgery. Malicious payload such as HTML containing JavaScript might be provided by either an authenticated backend user or by a non-authenticated user using a third party extension, e.g. file upload in a contact form with knowing the target location. To be successful, the attacked victim requires an active

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References