Stack-based buffer overflow in the cons_options function in options.c in dhcpd in OpenBSD 4.0 through 4.2, and some other dhcpd implementations based on ISC dhcp-2, allows remote attackers to execute arbitrary code or cause a denial of service (daemon crash) via a DHCP request specifying a maximum message size smaller than the minimum IP MTU. The following exploit code can be used to test your DHCP server for the mentioned MMS issue (maximum message size).
http://www.securiteam.com/exploits/6Z00115KAQ.html
