The Messenger of Allah ﷺ said, "The worst two tribes among the Arabs are Najran and Banu Taghlib."
حدثنا أبو المغيرة حدثنا عثمان بن عبيد أبو دوس اليحصبي حدثنا عبد الرحمن بن عائذ الثمالي
قال رسول الله ﷺ شر قبيلتين في العرب نجران وبنو تغلب
Its chain of transmission is sahih. Uthman bin Ubayd is al-Yahsubi, whom Ibn Hibban deemed trustworthy, and the leading scholars accepted him. Abdul-Rahman bin Aaidh al-Thumali al-Himsi is a trustworthy figure among the Followers. Haythami said in 10/71, "The men of Ahmad's chain are trustworthy."