CVE 2011-2716
The DHCP client (udhcpc) in BusyBox before 1.20.0 allows remote DHCP servers to execute arbitrary commands via shell metacharacters in the (1) HOST_NAME, (2) DOMAIN_NAME, (3) NIS_DOMAIN, and (4) TFTP_SERVER_NAME host name options.
See the 
CVE page on Mitre.org
for more details.
