The parse_datetime function in GNU coreutils allows remote attackers to cause a denial of service (crash) or possibly execute arbitrary code via a crafted date string, as demonstrated by the "--date=TZ="123"345" @1" string to the touch or date command.
https://security.gentoo.org/glsa/201612-22
http://www.openwall.com/lists/oss-security/2014/11/25/4
http://ubuntu.com/usn/usn-2473-1