Our Qualys security scan has scanned our external port our concentrator and has this vulnerability:
Cisco Internet Key Exchange (IKE) is exposed to a denial of service issue. This issue affects devices implementing IKE Version 1, and is due to resource exhaustion when handling a high rate of IKE requests. An attack of 10 packets per second at 122 bytes each is sufficient to cause denial of service conditions.
Cisco is tracking these issues with the following Bug IDs:
* CSCse70811 for Cisco IOS software
* CSCse89808 for Cisco VPN 3000 Concentrators
* CSCsb51032 for Cisco PIX firewalls
A successful attack may lead to denial of service to legitimate users.