The telnet service in Cisco Video Surveillance IP Gateway Encoder/Decoder (Standalone and Module) firmware 1.8.1 and earlier, Video Surveillance SP/ISP Decoder Software firmware 1.11.0 and earlier, and the Video Surveillance SP/ISP firmware 1.23.7 and earlier does not require authentication, which allows remote attackers to perform administrative actions, aka CSCsj31729.
https://exchange.xforce.ibmcloud.com/vulnerabilities/36449
http://www.vupen.com/english/advisories/2007/3061
http://www.securitytracker.com/id?1018655
http://www.securityfocus.com/bid/25549
http://www.cisco.com/en/US/products/products_security_advisory09186a00808b4d38.shtml