OpenProject is an open-source, web-based project management software. Versions prior to 16.6.9, 17.0.6, 17.1.3, and 17.2.1 are vulnerable to an SQL injection attack via a custom field's name. When that custom field was used in a Cost Report, the custom field's name was injected into the SQL query without proper sanitation. This allowed an attacker to execute arbitrary SQL commands during the generation of a Cost Report. As custom fields can only be generated by users with full administrator privileges, the attack surface is somewhat reduced. Together with another bug in the Repositories_module, that used the project identifier without sanitation to generate the checkout path for a git repository in the filesystem, this allowed an attacker to checkout a git repository to an arbitrarily chosen path on the server. If the checkout is done within certain paths within the OpenProject application, upon the next restart of the application, this allows the attacker to inject ruby code into the application. As the project identifier cannot be manually edited to any string containing special characters like dots or slashes, this needs to be changed via the SQL injection described above. Versions 16.6.9, 17.0.6, 17.1.3, and 17.2.1 fix the issue.