Unspecified vulnerability in Microsoft Powerpoint allows remote user-assisted attackers to execute arbitrary code via unknown attack vectors, as exploited by Trojan.PPDropper.G.  NOTE: as of 20070213, it is not clear whether this is the same issue as CVE-2006-5296, CVE-2006-4694, CVE-2006-3876, CVE-2006-3877, or older issues.