Cisco IOS 12.2 and 12.3 on Cisco uBR10012 series devices, when linecard redundancy is configured, enables a read/write SNMP service with "private" as the community, which allows remote attackers to obtain administrative access by guessing this community and sending SNMP requests.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A5452
http://www.vupen.com/english/advisories/2008/2670
http://www.cisco.com/en/US/products/products_security_advisory09186a0080a014b1.shtml