I want to break my lease due to foreclosure, what are my rights as a renter? Do I have to abide the lease terms even though the landlord is at fault?

As long as the landlord is the owner, the lease is valid and needs to be abided by. What makes you say the landlord is "at fault".

If you live in California, there is some protection here. There is a sticky note at the top of this forum that discusses it.

If the property is foreclosed on, your lease will be voided, but you will have 90 days to find a new place.