Buffer overflow in BL4 SMTP Server 0.1.4 and earlier allows remote attackers to cause a denial of service (crash) or execute arbitrary code via a long argument to the (1) EHLO, (2) MAIL FROM, and (3) RCPT TO commands.
https://exchange.xforce.ibmcloud.com/vulnerabilities/26114
http://www.securityfocus.com/archive/1/432329/100/0/threaded