Cisco IOS on Catalyst 3750X switches has default Service Module credentials, which makes it easier for local users to gain privileges via a Service Module login, aka Bug ID CSCue92286.
https://euvd.enisa.europa.eu/vulnerability/EUVD-2013-5362
http://tools.cisco.com/security/center/content/CiscoSecurityNotice/CVE-2013-5522