Recently a hacker was able to get source code of VMware ESX and as a proof posted a file on a website. The hacker announced he will post all source code at May 5. Read more about this here.
As a result VMware posted several blogs about this and accelerated the delivery of a set of software patches.
Taken from this posting at VMware.com
On April 23, 2012, our security team became aware of the public posting of a single file from the VMware ESX source code dating back to 2004, and the possibility that more files may be posted in the near future. Ensuring customer security is our top priority. As a matter of best practices with respect to security, VMware strongly encourages all customers to apply the latest product updates and security patches made available for their specific environment. As part of its regular program of providing patches for security and other issues, VMware has accelerated the delivery of a set of software patches for specific product releases that may be exposed to increased risk. We encourage all customers to view the following links to determine if appropriate patches are available for products in their environment: http://kb.vmware.com/kb/2019941 and http://www.vmware.com/security/advisories/VMSA-2012-0009.html.
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