The Sun SPARC Enterprise M4000 and M5000 Server, within a certain range of serial numbers, allows remote attackers to use the manufacturing root password, perform a root login to the eXtended System Control Facility Unit (aka XSCFU or Service Processor), and have unspecified other impact.
http://www.vupen.com/english/advisories/2009/0207
http://www.securitytracker.com/id?1021602
http://www.securityfocus.com/bid/33280
http://sunsolve.sun.com/search/document.do?assetkey=1-26-249126-1