CVE-2023-24814 Persisted Cross-Site Scripting in Frontend Rendering in typo3

What is CVE-2023-24814?

CVE-2023-24814 is a high-severity cross-site scripting vulnerability in Typo3 Typo3, published on 7 Feb 2023. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

TYPO3 is a free and open source Content Management Framework released under the GNU General Public License. In affected versions the TYPO3 core component `GeneralUtility::getIndpEnv()` uses the unfiltered server environment variable `PATH_INFO`, which allows attackers to inject malicious content. In combination with the TypoScript setting `config.absRefPrefix=auto`, attackers can inject malicious HTML code to pages that have not been rendered and cached, yet. As a result, injected values would be cached and delivered to other website visitors (persisted cross-site scripting). Individual code which relies on the resolved value of `GeneralUtility::getIndpEnv('SCRIPT_NAME')` and corresponding usages (as shown below) are vulnerable as well. Additional investigations confirmed that at least Apache web server deployments using CGI (FPM, FCGI/FastCGI, and similar) are affected. However, there still might be the risk that other scenarios like nginx, IIS, or Apache/mod_php are vulnerable. The usage of server environment variable `PATH_INFO` has been removed from corresponding processings in `GeneralUtility::getIndpEnv()`. Besides that, the public property `TypoScriptFrontendController::$absRefPrefix` is encoded for both being used as a URI component and for being used as a prefix in an HTML context. This mitigates the cross-site scripting vulnerability. Users are advised to update to TYPO3 versions 8.7.51 ELTS, 9.5.40 ELTS, 10.4.35 LTS, 11.5.23 LTS and 12.2.0 which fix this problem. For users who are unable to patch in a timely manner the TypoScript setting `config.absRefPrefix` should at least be set to a static path value, instead of using auto - e.g. `config.absRefPrefix=/`. This workaround **does not fix all aspects of the vulnerability**, and is just considered to be an intermediate mitigation to the most prominent manifestation.

Weakness: CWE-79

Which versions are affected by CVE-2023-24814?

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

Products include Typo3 Typo3.

How do I fix CVE-2023-24814?

Upgrade typo3/cms-core to a fixed version for your release line: 10.4.36, 11.5.23, 12.2.0 or 8.7.51.

Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.

Is CVE-2023-24814 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-24814 exists.

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-2021-41113 Cross-Site-Request-Forgery in Backend URI Handling in Typo3 High 8.8
• CVE-2020-15098 Missing Required Cryptographic Step Leading to Sensitive Information Disclosure in TYPO3 CMS High 8.8

All Typo3 Typo3 vulnerabilities

Sources

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

Also known as BIT-typo3-2023-24814, GHSA-r4f8-f93x-5qh3.