The VPN software within HP ThinPro does not safely handle user supplied input, which may be leveraged by an attacker to inject commands that will execute with root privileges.
https://support.hp.com/us-en/document/c06509350
http://seclists.org/fulldisclosure/2020/Mar/39
http://packetstormsecurity.com/files/156907/HP-ThinPro-6.x-7.x-Citrix-Command-Injection.html