The ability for the platform to understand programmes in different languages makes the threat from worms and trojans much greater, as many of these are written in other languages such as Perl and currently have no anti-virus products.
It's rather amusing that this statement is in direct contradiction with one of the major features of the .NET architecture: the Common Language Runtime. Microsoft writes that code built upon CLR benefits from features such as cross-language integration. A little further down, it is stated that The common language runtime makes it easy to design components and applications whose objects interact across languages. Objects written in different languages can communicate with each other, and their behaviors can be tightly integrated. .
Clearly one of the key features in CLR is the ability to mix different languages. Did the author of the paper miss out on such an important feature? Or is the language we monks all love perhaps too different?