Muwatta Malik · Hadith 1853
حَدَّثَنِي عَنْ مَالِكٍ، أَنَّهُ بَلَغَهُ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " لاَ تَحِلُّ الصَّدَقَةُ لآلِ مُحَمَّدٍ إِنَّمَا هِيَ أَوْسَاخُ النَّاسِ " .
Yahya related to me from Malik that he heard that the Messenger of Allah, may Allah bless him and grant him peace, said, "Sadaqa to the family of Muhammad is not halal. It is only people's impurities
Sahih · Salim al-Hilali