Ok, it's not really a SciHub for standards, but it is in the same spirit. Most people don't order standards from the ISO, they get them from their organization's (university or corporation) library. Very much the same as for papers.

What can you do if you are not affiliated with any organization that provides access? You can turn for SciHub for papers and to LibGen as your library. Needless to mention that both are infringing copyright and may or may not be legal for you to use.