XWEB EVO versions 5.2.3 through before 5.7.0 contains a pre-authentication OS command injection vulnerability that allows unauthenticated remote attackers to execute arbitrary OS commands by injecting shell metacharacters into the username field of login.lua, cleanout.lua, or api.lua before the password check occurs. Attackers can exploit this flaw combined with the setuid-root wlua interpreter to execute commands with root privileges, achieving full system compromise. This product line reached it's end of service date in March 2026.