Path Traversal Vulnerability in hap-wi/roxy-wi

hap-wi/roxy-wi is a web interface for managing Haproxy, Nginx, Apache and Keepalived servers. A Path Traversal vulnerability was found in the current version of Roxy-WI (6.3.9.0 at the moment of writing this report). The vulnerability can be exploited via an HTTP request to /app/options.py and the config_file_name parameter. Successful exploitation of this vulnerability could allow an attacker with user level privileges to obtain the content of arbitrary files on the file server within the scope of what the server process has access to. The root-cause of the vulnerability lies in the get_config function of the /app/modules/config/config.py file, which only checks for relative path traversal, but still allows to read files from absolute locations passed via the config_file_name parameter.