Multiple heap-based buffer overflows in the ApiThread function in the firewall service (aka TmPfw.exe) in Trend Micro Network Security Component (NSC) modules, as used in Trend Micro OfficeScan 8.0 SP1 Patch 1 and Internet Security 2007 and 2008 17.0.1224, allow remote attackers to execute arbitrary code via a packet with a small value in an unspecified size field.