Polycom MGC 25 allows remote attackers to cause a denial of service (crash) via a large number of "user" requests to the control port 5003, as demonstrated using the blast TCP stress tester.
The web server for Polycom ViaVideo 2.2 and 3.0 allows remote attackers to cause a denial of service (CPU consumption) by sending incomplete HTTP requests and leaving the connections open.
The Telnet service for Polycom ViewStation before 7.2.4 allows remote attackers to cause a denial of service (crash) via long or malformed ICMP packets.
The Telnet service for Polycom ViewStation before 7.2.4 allows remote attackers to cause a denial of service (crash) via multiple connections to the server.