The following paper lists several severe vulnerabilities with Cisco systems’ SIP-based IP Phone 7960 and its supporting environment. These vulnerabilities lead to complete control of a user’s credentials, the total subversion of a user’s settings for the IP Telephony network, and the ability to subvert the entire IP Telephony environment. Malicious access to a user’s credentials could enable "Call Hijacking", "Registration Hijacking", "Call Tracking", and other voice related attacks. The vulnerabilities exist with any deployment scenario, but this paper deals specifically with large scale deployments as recommended by Cisco.
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