CVE 2006-4455
** DISPUTED ** Unspecified vulnerability in Xchat 2.6.7 and earlier allows remote attackers to cause a denial of service (crash) via unspecified vectors involving the PRIVMSG command. NOTE: the vendor has disputed this vulnerability, stating that it does not affect 2.6.7 "or any recent version".
See the 
CVE page on Mitre.org
for more details.
