Avi Alkalay notify program, dated 19 Aug 2001, allows remote attackers to execute arbitrary commands via shell metacharacters in the from parameter.
https://exchange.xforce.ibmcloud.com/vulnerabilities/22353
http://www.vupen.com/english/advisories/2005/1809
http://www.securityfocus.com/bid/14893
http://www.cirt.net/advisories/alkalay.shtml