LinuxSecurity.com: A vulnerability has been found and corrected in dhcp:
ISC DHCP 4.1 before 4.1.1-P1 and 4.0 before 4.0.2-P1 allows remote
attackers to cause a denial of service (server exit) via a zero-length
client ID (CVE-2010-2156).
The network was fine yesterday and as far as I know nothing has been changed or added. This morning some computers are connected to our domain but most of them are reporting limited connectivity. On checking our DHCP server we are getting this message.