The Update Installer in VMware ESXi 4.1, when a modified sfcb.cfg is present, does not properly configure the SFCB authentication mode, which allows remote attackers to obtain access via an arbitrary username and password.
kb.vmware.com/kb/1031761
lists.vmware.com/pipermail/security-announce/2010/000114.html
secunia.com/advisories/42591
securitytracker.com/id?1024917
www.securityfocus.com/archive/1/515420/100/0/threaded
www.securityfocus.com/bid/45543
www.vmware.com/security/advisories/VMSA-2010-0020.html
www.vupen.com/english/advisories/2010/3303