Abu Ashath reported,

Some men stood up to give speeches in Sham, among them were companions of the Messenger of Allah ﷺ. The last to stand was a man called Mura bin Kaab, who said, "Were it not for a hadith I heard from the Messenger of Allah ﷺ, I would not have stood up."He spoke of the tribulations and described them as being near at hand. Then a man passed by, wrapped up in a garment, and the Messenger of Allah ﷺ said, "This man, on that day, will be upon guidance."So I got up and went to him, and there he was, Uthman bin Affan.He said, I turned him by his face toward me and asked, "This one?"He replied, "Yes."

Azami 9906

Sahih

عن أبي الأشعث الصنعاني

أن خطباء قامت بالشام، وفيهم رجال من أصحاب رسول الله ﷺ، فقام آخرهم رجل يقال له: مرة بن كعب، فقال: لولا حديث سمعته من رسول الله ﷺ ما قمت، وذكر الفتن فقربها، فمر رجل مقنع في ثوب فقال: هذا يومئذ على الهدى، فقمت إليه فإذا هو عثمان بن عفان. قال: فأقبلت عليه بوجهه، فقلت: هذا؟ قال: نعم.

الأعظمي 9906صحيح
Contents
Reference
Commentary
Ayat
Collection
Jami al-Kamil
Book
Virtues of the Companions and reports about them
Chapter
Virtues of Uthman bin Affan and reports about him
Section
His saying, "Uthman will be killed unjustly"
Numbering
Jami al-Kamil 9906 (2nd edition)
Azami 9906