This article first touches upon the notion of cyber terrorism in the context of the relevant international framework and the recent cyber attacks against Estonia by addressing issues of the dependence of a society on ICT. The purpose of such an introduction is better to explain the international debate on prosecution and prevention of cyber terrorism. In the author's opinion, effective prevention of cyber terrorism needs to be performed on a national level. Therefore the third main subject of this article is the (inter)national legal framework of preventing cyber terrorist acts and the prospect of the legal and practical problems that countries may face when addressing this mostly cross-border problem area.