The PIIX4 power management subsystem in EMC VMware Workstation 5.5.3.34685 and VMware Server 1.0.1.29996 allows local users to write to arbitrary memory locations via a crafted poke to I/O port 0x1004, triggering a denial of service (virtual machine crash) or other unspecified impact, a related issue to CVE-2007-1337.