Now, the good news is that you did not steal someone's identity or used false number or submitted fake documents, all of which are separate crimes. So you are better off than many other DREAMers who have done all of these including working without authorization. As far as working with a Social Security number that does not authorize you to work, you have definitely broken the law, though, what you can be charged with depends on the prosecutors (at this time it is not clear if USCIS will refer these cases for action or simply reject the applications or even approve them considering that this is not going to give you any legal status and only defers deportation), but just as an example, here are a few that you could be charged with:
- Using false documents to be employed: A maximum penalty of 10 years without parole in federal prison and a fine up to $250,000.
- Making a false statement on an I-9: A maximum penalty of 5 years in federal prison without parole and a fine up to $250,000.
- Misusing a Social Security number: A maximum penalty of 5 years in federal prison without parole and a fine up to $250,000.
I would say that you should consult an attorney who is well versed in immigration, Social Security, and tax matters (don't just call an attorney to discuss filing your DACA application but schedule a consultation for an hour and pay for it) and then find out all the implications for you. For someone like you who has lived for so long like this, it might be better to wait (till we find out what USCIS decides in similar cases) or simply hope for action from Congress in which such problems will be forgiven. When President issued this executive order, he was merely trying to help otherwise law-abiding undocumented youth but he has no authority to grant an amnesty.