ISC DHCP client program dhclient allows remote attackers to execute arbitrary commands via shell metacharacters.
ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/advisories/FreeBSD-SA-00:34.dhclient.asc
ftp://ftp.NetBSD.ORG/pub/NetBSD/misc/security/advisories/NetBSD-SA2000-008.txt.asc
archives.neohapsis.com/archives/bugtraq/2000-06/0247.html
archives.neohapsis.com/archives/bugtraq/2000-07/0014.html
www.debian.org/security/2000/20000628
www.novell.com/linux/security/advisories/suse_security_announce_56.html
www.securityfocus.com/bid/1388
exchange.xforce.ibmcloud.com/vulnerabilities/4772