Multiple format string vulnerabilities in the DCC functionality in KVIrc 3.4 and 4.0 have unspecified impact and remote attack vectors.
http://www.vupen.com/english/advisories/2010/1602
http://www.securityfocus.com/bid/40746
http://www.debian.org/security/2010/dsa-2065
http://secunia.com/advisories/40349
http://secunia.com/advisories/32410
http://lists.opensuse.org/opensuse-security-announce/2010-08/msg00001.html
http://lists.omnikron.net/pipermail/kvirc/2010-May/000867.html
http://lists.fedoraproject.org/pipermail/package-announce/2010-June/043629.html
http://lists.fedoraproject.org/pipermail/package-announce/2010-June/043601.html