Buffer overflow in pop3svr.exe for DMS POP3 1.5.3.27 and earlier allows remote attackers to cause a denial of service (service crash) via a long (1) username or (2) password.
https://exchange.xforce.ibmcloud.com/vulnerabilities/18161
https://euvd.enisa.europa.eu/vulnerability/EUVD-2004-1527
http://www.securityfocus.com/bid/11705
http://www.digitalmapping.sk.ca/pop3srv/Update.asp