A buffer overflow in Smart Card authentication code in gpkcsp.dll in Microsoft Windows XP through SP3 and Server 2003 through SP2 allows a remote attacker to execute arbitrary code on the target computer, provided that the computer is joined in a Windows domain and has Remote Desktop Protocol connectivity (or Terminal Services) enabled.
https://blogs.technet.microsoft.com/msrc/2017/04/14/protecting-customers-and-evaluating-risk/
https://blog.fortinet.com/2017/05/11/deep-analysis-of-esteemaudit
https://blog.0patch.com/2017/06/a-quick-analysis-of-microsofts.html