Equation Group is the name given by AV vendors to a group of attacks thought to be carried out by NSA. This is, apparently, a dump of internal files (mostly exploits and command & control scripts) that someone got ahold of. They're now apparently trying to auction them off.
If it's a fake, it's a very good one – the code words match up to things we've seen in the Snowden leaks, e.g. Jetplow (https://www.schneier.com/blog/archives/2014/01/jetplow_nsa_e...). Matthieu Suiche has a good initial writeup here:
https://medium.com/@msuiche/shadow-brokers-nsa-exploits-of-t...