The Trend Micro AntiVirus scan engine before 8.550-1001, as used in Trend Micro PC-Cillin Internet Security 2007, and Tmxpflt.sys 8.320.1004 and 8.500.0.1002, has weak permissions (Everyone:Write) for the \\.\Tmfilter device, which allows local users to send arbitrary content to the device via the IOCTL functionality. NOTE: this can be leveraged for privilege escalation by exploiting a buffer overflow in the handler for IOCTL 0xa0284403.
http://www.vupen.com/english/advisories/2007/3627
http://www.securityfocus.com/bid/26209
http://securitytracker.com/id?1018863
http://secunia.com/advisories/27378
http://labs.idefense.com/intelligence/vulnerabilities/display.php?id=609
http://esupport.trendmicro.com/support/viewxml.do?ContentID=1036190
http://esupport.trendmicro.com/support/viewxml.do?ContentID=1035793