Can a first mortgage foreclose with a second?
Yes. The second is subordinate to the first mortgage and
therefore is at greater risk. If equity exists, the 2nd mortgage
holder may receive payment for the debt when a senior lender
forecloses. If there is not, then their lien on the property is
wiped out and they must pursue the borrower in another fashion
(such as a lawsuit). If the 2nd mortgage lender does not want the
1st lender to foreclose, they may choose to pay the 1st mortgage
current before the foreclosure proceeds and attempt to collect or
foreclose themselves.