Unspecified vulnerability in the "session limitation technique" in the FTP service on Nortel Communications Server 1000 (CS1K) 4.50.x, when running on VGMC or signaling nodes, allows remote attackers to cause a denial of service (resource exhaustion and failed updates) via unknown vectors that causes consumption of all available sessions.
https://exchange.xforce.ibmcloud.com/vulnerabilities/41804
http://www.voipshield.com/research-details.php?id=11
http://www.securityfocus.com/bid/28691
http://support.nortel.com/go/main.jsp?cscat=BLTNDETAIL&id=713455
http://securitytracker.com/id?1019845