Sahih al-Bukhari 6966
صحيح البخاري#6966Sahihحَدَّثَنَا أَبُو نُعَيْمٍ، حَدَّثَنَا سُفْيَانُ، عَنْ عَبْدِ اللَّهِ بْنِ دِينَارٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ ـ رضى الله عنهما ـ عَنِ النَّبِيِّ صلى الله عليه وسلم " لِكُلِّ غَادِرٍ لِوَاءٌ يَوْمَ الْقِيَامَةِ يُعْرَفُ بِهِ ".
Narrated `Abdullah bin `Umar:The Prophet (ﷺ) said, "For every betrayer there will be a flag by which he will be recognized on the Day of Resurrection
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
Every narration in Sahih al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 90:13