Security Watch
September 23, 2008
By Alan Harten
StrongSwan is an open source IPsec-based virtual private network (VPN) solution
for the Linux operating system.
IPsec-based VPNs secure corporate VoIP, email, web, IPTV and other IP-based services
over public network infrastructures.
On the 16th of this month StrongSwan’s IKEv2 implementation was found by
Mu Dynamics to have a very serious and dangerous 0-day vulnerability.
The IKEv2
needed to establish VPN connectivity as this is essential to authenticate users
and establish session keys.
Mu Labs identified what it suspected was an anonymous attacker, that was at
least unauthenticated and in their opinion was capable of crashing VPN terminator
or other IPsec devices, and this could be done using just the very first IKEv2
packet.
Luckily Mu and strongSwan were able to produce a patch over a period of 14
hours to remove the problem.
The company believes that other IKEv2 implementations are at risk of similar
attacks.
In order to prevent IPsec VPN service downtime IKEv2 implementations must be
subjected to variations on real world service-level traffic throughout the
deployment life cycle.