N.J. Stat. Ann. § 2A:42-10

Nothing contained in sections 2A:42-7 and 2A:42-8 of this title shall extend to bar the right of a mortgagee of such lease, or any part thereof, who shall not be in possession, if he shall, within 6 months after judgment is obtained and execution executed, pay all rent in arrear, costs and damages sustained by the lessor, or person entitled to the remainder or reversion and perform the covenants and agreements which on the part and behalf of the first lessee should be performed.