Sahih al-Bukhari 3355
Narrated Mujahid:
That when the people mentioned before Ibn 'Abbas that the Dajjal would have the word Kafir, (i.e. unbeliever) or the letters Kafir (the root of the Arabic verb 'disbelieve') written on his forehead, I heard Ibn 'Abbas saying, "I did not hear this, but the Prophet ﷺ said, 'If you want to see Abraham, then look at your companion (i.e. the Prophet) but Moses was a curly-haired, brown man (who used to ride) a red camel, the reins of which was made of fires of date-palms. As if I were now looking down a valley."
حَدَّثَنِي بَيَانُ بْنُ عَمْرٍو، حَدَّثَنَا النَّضْرُ، أَخْبَرَنَا ابْنُ عَوْنٍ، عَنْ مُجَاهِدٍ، أَنَّهُ سَمِعَ ابْنَ عَبَّاسٍ ـ رضى الله عنهما ـ وَذَكَرُوا لَهُ الدَّجَّالَ بَيْنَ عَيْنَيْهِ مَكْتُوبٌ كَافِرٌ أَوْ ك ف ر. قَالَ لَمْ أَسْمَعْهُ وَلَكِنَّهُ قَالَ " أَمَّا إِبْرَاهِيمُ فَانْظُرُوا إِلَى صَاحِبِكُمْ، وَأَمَّا مُوسَى فَجَعْدٌ آدَمُ عَلَى جَمَلٍ أَحْمَرَ مَخْطُومٍ بِخُلْبَةٍ، كَأَنِّي أَنْظُرُ إِلَيْهِ انْحَدَرَ فِي الْوَادِي ".