Estate Law Questions? Ask an Estate Lawyer.
As the Executor you have a fiduciary duty to maintain and manage the Estate. The Estate "owns" the property until it is distributed to the beneficiaries. Once it is distributed the beneficiaries together decide what to do with the property, until then you do what is in the best interest of the beneficiaries and Estate, and follow the terms of the Will. If there is no Will, you follow the laws of intestacy in your State.
Your thought about contacting the bank is exactly what you should do, and then you should present what you are told to your brother. You say that 'you' cannot afford to pay, but your brother has 1/2 interest so he must help pay too, if there are no funds available in the Estate itself. You must keep your brother informed as to the situation with the house, otherwise, yes you are opening yourself up to liability. However, it is still your ultimate decision in regards XXXXX XXXXX estate, and as long as you could defend your actions as reasonable under the circumstances and then you should be fine.