CVE 2012-3954
Multiple memory leaks in ISC DHCP 4.1.x and 4.2.x before 4.2.4-P1 and 4.1-ESV before 4.1-ESV-R6 allow remote attackers to cause a denial of service (memory consumption) by sending many requests.
See the 
CVE page on Mitre.org
for more details.
