Magento Long Term Support (LTS) is an unofficial, community-driven project provides an alternative to the Magento Community Edition e-commerce platform with a high level of backward compatibility. Prior to version 20.17.0, the Dataflow module in OpenMage LTS uses a weak blacklist filter ("str_replace('../', '', $input)") to prevent path traversal attacks. This filter can be bypassed using patterns like "..././" or "....//", which after the replacement still result in "../". An authenticated administrator can exploit this to read arbitrary files from the server filesystem. Version 20.17.0 patches the issue.