Stack-based buffer overflow in Justsystem Ichitaro 9.x through 13.x, Ichitaro 2004, 2005, 2006, and Government 2006; Ichitaro for Linux; and FormLiner before 20060818 allows remote attackers to execute arbitrary code via long Unicode strings in a crafted document, as being actively exploited by malware such as Trojan.Tarodrop. NOTE: some details are obtained from third party information.