VMware Tools in VMware Workstation 10.x before 10.0.2, VMware Player 6.x before 6.0.2, VMware Fusion 6.x before 6.0.3, and VMware ESXi 5.0 through 5.5, when a Windows 8.1 guest OS is used, allows guest OS users to gain guest OS privileges or cause a denial of service (kernel NULL pointer dereference and guest OS crash) via unspecified vectors.