Cisco IP Phone (VoIP) 7920 1.0(8) contains certain hard-coded ("fixed") public and private SNMP community strings that cannot be changed, which allows remote attackers to obtain sensitive information.
https://exchange.xforce.ibmcloud.com/vulnerabilities/23067
https://euvd.enisa.europa.eu/vulnerability/EUVD-2005-3798
http://www.securityfocus.com/bid/15454
http://www.cisco.com/warp/public/707/cisco-sa-20051116-7920.shtml