Format string vulnerability in the URI handler in KVirc 3.4.0, when set as the default application for processing IRC URIs, allows remote attackers to cause a denial of service (application crash) and possibly execute arbitrary code via format string specifiers in the irc:// URI.
https://www.exploit-db.com/exploits/6832
https://exchange.xforce.ibmcloud.com/vulnerabilities/46114
http://www.vupen.com/english/advisories/2008/2926
http://www.securityfocus.com/bid/31912