Gadu-Gadu 7.20 allows remote attackers to eavesdrop on a user via a web page that accesses the EasycallLite.oce ActiveX control, which can initiate an outgoing phone call and listen to the microphone.
http://www.securityfocus.com/bid/15520/
http://secunia.com/advisories/17597/
http://marc.info/?l=bugtraq&m=113261573023912&w=2
http://archives.neohapsis.com/archives/fulldisclosure/2005-11/0658.html