I'm not a lawyer. But I think if your "binary patch" is a series of instructions to write specific code to specific locations in a binary file, and the patch itself doesn't include any of the code present in the original binary, making/distributing a binary patch can't possibly be copyright infringement.

It's normal in the videogame ROM hacking community to distribute this kind of binary patches (known as IPS patches) so as to avoid legal trouble, since the binary patch is useless if the user doesn't have access to the original videogame ROM. Distributing the ROM or even its patched version would be illegal, but a patch of the kind I mentioned is fine.

CFAA and friends (in the US, at least) means that even things you might not otherwise expect are illegal get turned into super illegal.

Binary patches are probably fine to make, but to distribute them for other people's binaries is probably not.