Cisco NX-OS 6.0(2)U6(1) through 6.0(2)U6(5) on Nexus 3000 devices and 6.0(2)A6(1) through 6.0(2)A6(5) and 6.0(2)A7(1) on Nexus 3500 devices has hardcoded credentials, which allows remote attackers to obtain root privileges via a (1) TELNET or (2) SSH session, aka Bug ID CSCuy25800.
https://isc.sans.edu/forums/diary/20795
http://www.securitytracker.com/id/1035161
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160302-n3k