In this paper, we present recent research on internet
threats aiming at fraud or hampering critical information infrastructure. One approach concentrates on the
rapid detection of phishing email, designed to make it next impossible for attackers to obtain financial
resources or commit identity theft in this way. Then we address how another type of internet fraud, the
violation of the rights of trademark owners by faked merchandise, can be semi-automatically solved with
text mining methods. Thirdly, we report on two projects that are designed to prevent fraud in business
processes in public administrations, namely in the healthcare sector and in customs administrations. Finally,
we focus on the issue of critical infrastructures, and describe our approach towards protecting them using a
specific middleware architecture.