Roxy-WI is a web interface for managing Haproxy, Nginx, Apache and Keepalived servers. Prior to version 8.2.6.4, the POST /config/<service>/show API endpoint accepts a configver parameter that is directly appended to a base directory path to construct a local file path, which is subsequently opened and its contents returned to the caller. The existing path traversal guard only inspects the base directory variable (which is never user-controlled) and entirely ignores the user-supplied configver value.

An authenticated attacker can supply a configver value containing ../ sequences to escape the intended directory and read arbitrary files accessible to the web application process. Version 8.2.6.4 contains a patch for the issue.