Unspecified vulnerability in the CPU hardware emulation for 64-bit guest operating systems in VMware Workstation 6.0.x before 6.0.5 build 109488 and 5.x before 5.5.8 build 108000; Player 2.0.x before 2.0.5 build 109488 and 1.x before 1.0.8; Server 1.x before 1.0.7 build 108231; and ESX 2.5.4 through 3.5 allows authenticated guest OS users to gain additional guest OS privileges via unknown vectors that cause "the virtual CPU to jump to an incorrect memory address."

More... (http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2008-4279)