Cisco Catalyst 4000, 6000, and 6500 switches contains a flaw that may allow a malicious user to gain access to unauthorized privileges. The issue is triggered due an an error in the local authentication mechanism. This flaw may lead to a loss of Integrity.
Upgrade to version 7.5.2 or higher, as it has been reported to fix this vulnerability. It is also possible to correct the flaw by implementing the following workaround(s): enable AAA Authentication, Apply an ACL access control list to prevent telnet access.