RatPanel is a server operation and maintenance management panel. In versions 2.3.19 through 2.5.5, when an attacker obtains the backend login path of RatPanel (including but not limited to weak default paths, brute-force cracking, etc.), they can execute system commands or take over hosts managed by the panel without logging in. In addition to this remote code execution (RCE) vulnerability, the flawed code also leads to unauthorized access. RatPanel uses the CleanPath middleware provided by github.com/go-chi/chi package to clean URLs, but but the middleware does not process r.URL.Path, which can cause the paths to be misinterpreted. This is fixed in version 2.5.6.
The authentication algorithm is sound, but the implemented mechanism can be bypassed as the result of a separate weakness that is primary to the authentication error.