The Board Management Controller (BMC) in the Serial over LAN (SoL) subsystem in Cisco Unified Computing System (UCS) relies on a hardcoded private key, which allows man-in-the-middle attackers to obtain sensitive information or modify the data stream by leveraging knowledge of this key, aka Bug ID CSCte90338.
http://www.securitytracker.com/id/1029073
http://tools.cisco.com/security/center/content/CiscoSecurityNotice/CVE-2012-4074