HTML interface for Cisco VPN 3000 Concentrator 2.x.x and 3.x.x before 3.0.3(B) allows remote attackers to cause a denial of service (CPU consumption) via a long URL request.
http://www.securityfocus.com/bid/5615
http://www.iss.net/security_center/static/10018.php
http://www.cisco.com/warp/public/707/vpn3k-multiple-vuln-pub.shtml