A privilege escalation vulnerability exists in SolarWinds Serv-U before 15.1.7 for Linux.
https://blog.vastart.dev/2019/06/cve-2019-12181-serv-u-exploit-writeup.html
http://packetstormsecurity.com/files/153333/Serv-U-FTP-Server-15.1.6-Privilege-Escalation.html