The web server for Cisco IP Phone (VoIP) models 7910, 7940, and 7960 allows remote attackers to cause a denial of service (reset) and possibly read sensitive memory via a large integer value in (1) the stream ID of the StreamingStatistics script, or (2) the port ID of the PortInformation script.
http://www.securityfocus.com/bid/4798
http://www.securityfocus.com/bid/4794
http://www.iss.net/security_center/static/9143.php
http://www.iss.net/security_center/static/9142.php
http://www.cisco.com/warp/public/707/multiple-ip-phone-vulnerabilities-pub.shtml