The ipsec-tools package is used in conjunction with the IPsec functionality in the linux kernel and includes racoon, an IKEv1 keying daemon.
A denial of service flaw was found in the ipsec-tools racoon daemon. If a victim's machine has racoon configured in a non-recommended insecure manner, it is possible for a remote attacker to crash the racoon daemon. (CVE-2005-3732)
Users of ipsec-tools should upgrade to these updated packages, which contain backported patches, and are not vulnerable to these issues.