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 …