[evilDagmar]

Not under US Copyright law, but that's because you have a licence to the software which means you have the fair use right to take this security measure.

Absent a rather dubious user agreement allowing Facebook to copy all the data off your phone, Facebook does not have that fair use right. Nor is it likely even remotely ethical to be doing this without explicitly notifying the user. So, illegal and unethical, but I guess unless some PR firm is paying the news media to be outraged about it, they're not likely to care.