ENOfficial
Shu’bah said in his version: “the letters k, f, r” (are on his forehead).
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، عَنْ مُحَمَّدِ بْنِ جَعْفَرٍ، عَنْ شُعْبَةَ، ك ف ر .
sunnah.com
Sunan Abi Dawud
Book 39Hadith Number 4317