I am interested in US law as well as European law, and curious about international/other countries law, if applicable.
It is generally accepted that if you somehow find a private key (let's assume by reverse-engineering for now), you can't publish it. For example, this question takes it as a given.
However, I don't see what exactly in the law prevents from doing so. If you are given a piece of hardware or software that contains the key, it actually seems to me that there is nothing to prevent the key from being redistributed?
As far as I know copyright requires the material to be a creative work, with some originality. While the originality could be argued, I am not sure the creative work part would held. Moreover, it is well established that facts are not copyrightable. Can't a key be considered a fact?
The key can certainly not be patented, but it can be considered a trade secret. As this trade secret was not acquired trough unlawful means (such as an NDA breach), couldn't it be disclosed?
I am interested in legal precedents on the matter as well, if you know of any.