"The Prophet recited Fatihatil-Kitab for a funeral (prayer)." (Da'if Jiddan)  

أَنَّ النَّبِيَّ ﷺ قَرَأَ عَلَى الْجَنَازَةِ بِفَاتِحَةِ الْكِتَابِ قَالَ وَفِي الْبَابِ عَنْ أُمِّ شَرِيكٍ  

"Ibn Abbas performed Salat for a funeral and he recited Fatihatil-Kitab. So I asked him about it and he said: 'It is from the Sunnah' or, 'From the completeness of the Sunnah.'"  

إِنَّهُ مِنَ السُّنَّةِ أَوْ مِنْ تَمَامِ السُّنَّةِ