Check Point Checkpoint VPN-1 Firewall-1

Check Point VPN-1 Power/UTM, with NGX R60 through R65 and NG AI R55 software, allows remote authenticated users to cause a denial of service (site-to-site VPN tunnel outage), and possibly intercept network traffic, by configuring the local RFC1918 IP address to be the same as one of this tunnel's endpoint RFC1918 IP addresses, and then using SecuRemote to connect to a network interface at the other endpoint.

The design of the Internet Key Exchange (IKE) protocol, when using Aggressive Mode for shared secret authentication, does not encrypt initiator or responder identities during negotiation, which may allow remote attackers to determine valid usernames by (1) monitoring responses before the password is supplied or (2) sniffing, as originally reported for FireWall-1 SecuRemote.