Is it permissible to give zakat to an indebted brother to cover his house rent, knowing that he owns two houses and has huge debts, and he is owed money by the questioner and others?

It is permissible to give Zakat (definition) to a brother to pay his house rent if he is in debt and does not possess the means to pay off the debt, because he falls under the category of Zakat recipients known as "al-gharimun" (those in debt). It is important to note that this amount is not counted as part of any debt owed by the Zakat payer to his brother.