Certain ActiveX controls in (1) tsgetxu71ex552.dll and (2) tsgetx71ex552.dll in Tom Sawyer GET Extension Factory 5.5.2.237, as used in VI Client (aka VMware Infrastructure Client) 2.0.2 before Build 230598 and 2.5 before Build 204931 in VMware Infrastructure 3, do not properly handle attempted initialization within Internet Explorer, which allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a crafted HTML document.