HAX CMS helps manage microsite universe with PHP or NodeJs backends. Prior to version 26.0.0, an Authenticated Local File Inclusion (LFI) vulnerability in the HAXCMS saveOutline endpoint allows a low-privileged user to read arbitrary files on the server by manipulating the location field written into site.json. This enables attackers to exfiltrate sensitive system files such as /etc/passwd, application secrets, or configuration files accessible to the web server (www-data). Version 26.0.0 patches the issue.