Actually, there is no one “illuminati” group, however there are many groups and brotherhoods that have and use the arcane knowledge. (Arcanum Arcanorum)
Some groups use the Arcanum for obtaining enlightenment and helping others, and others use the same info to control people and dominate the planet.
There are no real “Illuminati Secrets” anymore from an esoteric standpoint.
Now a days you can find most of the secrets in the internet or in books if you know where to look.
(Even 50 years ago it was hard to get a book on Qabalah or magic and now all you have to do is Google it and there is an incredible selection to choose from.)
This is simply because in our modern world such esoteric info does not pose a threat to the establishment’s ability to control the masses anymore, so therefore the system no longer invests in keeping it secret.
Now a days the info that will get you in trouble is not when you know too much about Qabalah or Alchemy (Such as in the case of the Knights Templar for example…) but rather when you know too much about what corporations and governments are doing (i.e. big pharma, banks and defense contractors)