CVE-2006-3551
NCP Secure Enterprise Client (aka VPN/PKI client) 8.30 Build 59, and possibly earlier versions, when the Link Firewall and Personal Firewall are both configured to block all inbound and outbound network traffic, allows context-dependent attackers to send inbound UDP traffic with source port 67 and destination port 68, and outbound UDP traffic with source port 68 and destination port 67.
Date published : 2006-07-12
http://lists.grok.org.uk/pipermail/full-disclosure/2006-June/047547.html