Microsoft Windows Point-to-Point Tunneling Protocol (PPTP) is a network protocol from Microsoft Corporation that allows secure transmission of data from a remote client to a private enterprise server by creating a virtual private network (VPN) over a TCP/IP-based data network. A remote code execution vulnerability exists in Microsoft Windows Point-to-Point Tunneling Protocol, which stems from the failure of a network system or product to properly filter special elements of external input data during the construction of code segments, which can be exploited by an attacker to cause arbitrary code execution.