Cisco VPN Concentrator DoS Summary
The Cisco VPN 3000 series concentrators are a family of purpose-built, remote access Virtual Private Network (VPN) platforms for data encryption and authentication.
A malicious user may be able to send a crafted attack via SSL (Secure Sockets Layer) to the concentrators which may cause the device to reload, and/or drop user connections.
Repeated exploitation will create a sustained DoS (denial of service).
Workarounds are available to mitigate this vulnerability.
Cisco has made free software available to address this vulnerability for all affected customers.
This vulnerability is documented in the Cisco Bug Toolkit as Bug ID CSCeg11424 ( registered customers only)
This advisory is available at
Affected Products
Vulnerable Products
Cisco VPN 3000 series concentrators running software 4.1.7.A and earlier are affected by this vulnerability.
This series includes models 3005, 3015, 3020, 3030, 3060, 3080 and the Cisco VPN 3002 Hardware Client.
Products Confirmed Not Vulnerable
The following products are confirmed not vulnerable:
Cisco IPSec VPN Services Module (VPNSM)
Cisco VPN 5000 Concentrators
Cisco PIX Firewalls
Any Cisco device that runs Cisco’s Internetwork Operating System (IOS)
Any Cisco device that runs Cisco’s Catalyst Operating System (CatOS)
No other Cisco products are currently known to contain this vulnerability.