The ESX(i) 3.5 Update 2 Virtual Machine power on problem that surfaced today is not related to exploitation of a security issue on ESX. Several customers have been worried that their ESX systems had been compromised by an attack and that this was the cause for not booting of their ESX update 2 Virtual Machines today.
We know that the boot problem is due to an expired license. License expiration was set at August 12 and was not removed prior to releasing ESX(i) Update 2. VMotion is affected by the license expiration as well.
VMware is working very hard to get a patch out of the door. Please see here for a workaround and the latest developments.
Express patches have become available. Visit this VMware Web site for details.