As reported in the Guardian, Carrigan frets that alien radio signals could pose a security risk.
Why is it so difficult for one species to submit a technology virus to another, relatively unknown, species? Well, consider. We know nothing of their technology. We know nothign of their programming languages, code methodologies, or hardware/software. We know nothing of their communication methods — wireless, wired, etc. — and even if we knew what frequencies were used, it would be incredibly difficult to figure out what the sequence of 0’s and 1’s meant. Not to mention the fact that, even if we got past all that, we would know little about their security systems and, in turn, ways to thwart them.
Is it remotely possible? Yes. Considering infinite time and infinite events, anything can happen. But that’s hardly a reason to be concerned.
The best analogy I can give to this threat is this: What is the possibility that, upon finding a book filled with mysterious symbols that seem to follow a rough pattern of organization and, on occasion, repetition, but are otherwise totally mysterious, be translated into readable English? Sure, we can figure out Egyptian heiroglyphics, but we’re the same species, with similar cultures and language structures, and future languages developed from this historic language. We can figure out how some animals communicate by studying their behavior and language in natural and controlled environments — things we have no opportunity to do with ETs, especially those locusts who want to brutalize our planet (until Goldblum saves the day).