The IRC Protocol component in KVIrc 3.x and 4.x before r4693 does not properly handle \ (backslash) characters, which allows remote authenticated users to execute arbitrary CTCP commands via vectors involving \r and \40 sequences, a different vulnerability than CVE-2010-2451 and CVE-2010-2452.

Argument injection vulnerability in the URI handler in KVIrc 3.4.2 Shiny allows remote attackers to execute arbitrary commands via a " (quote) followed by command line switches in a (1) irc:///, (2) irc6:///, (3) ircs:///, or (4) and ircs6:/// URI. NOTE: this might be due to an incomplete fix for CVE-2007-2951.