Calisto Internet Talker 0.04 and earlier allows remote attackers to cause a denial of service (hang) via a long request, possibly triggering a buffer overflow.
https://exchange.xforce.ibmcloud.com/vulnerabilities/10694
http://www.securityfocus.com/bid/6238
http://securityreason.com/securityalert/3241
http://archives.neohapsis.com/archives/vulnwatch/2002-q4/0090.html