CVE-2020-11069 Cross-Site Request Forgery in TYPO3 CMS

What is CVE-2020-11069?

CVE-2020-11069 is a high-severity vulnerability in Typo3 Typo3, published on 13 May 2020. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

Official 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 and valid backend or install tool user session at the time of the attack. This has been fixed in 9.5.17 and 10.4.2. The deployment of additional mitigation techniques is suggested as described below. - Sudo Mode Extension This TYPO3 extension intercepts modifications to security relevant database tables, e.g. those storing user accounts or storages of the file abstraction layer. Modifications need to confirmed again by the acting user providing their password again. This technique is known as sudo mode. This way, unintended actions happening in the background can be mitigated. - https://github.com/FriendsOfTYPO3/sudo-mode - https://extensions.typo3.org/extension/sudo_mode - Content Security Policy Content Security Policies tell (modern) browsers how resources served a particular site are handled. It is also possible to disallow script executions for specific locations. In a TYPO3 context, it is suggested to disallow direct script execution at least for locations /fileadmin/ and /uploads/.

Weakness: CWE-352, CWE-346

Which versions are affected by CVE-2020-11069?

9 open source packages ship an affected version, including typo3/cms, typo3 and typo3/cms-core. It affects 1 product.

Products include Typo3 Typo3.

How do I fix CVE-2020-11069?

Upgrade typo3/cms to a fixed version for your release line: 10.4.2 or 9.5.17.

Is CVE-2020-11069 being exploited?

There is no known exploitation of CVE-2020-11069 in the wild and no public exploit code.

Other vulnerabilities in Typo3 Typo3

• CVE-2009-0258 Indexed Search Engine for TYPO3 Command Execution via Metacharacter Injection Critical 10.0
• CVE-2011-3583 Typo3 SQL injection due to faulty prepared statements Critical 9.8
• CVE-2011-4628 Typo3 Authentication Bypass Critical 9.8
• CVE-2023-24814 Persisted Cross-Site Scripting in Frontend Rendering in typo3 High 8.8
• CVE-2021-41113 Cross-Site-Request-Forgery in Backend URI Handling in Typo3 High 8.8

All Typo3 Typo3 vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BIT-typo3-2020-11069, GHSA-pqg8-crx9-g8m4.