Mus'ab bin Abdullah al-Zubayri said: Uthman bin Affan bin Abi al-As bin Umayyah bin Abd Shams bin Abd Manaf bin Qusayy bin Kilab bin Murrah bin Ka'b bin Lu'ayy bin Ghalib bin Fihr; his kunyah was Abu Amr, and he was also called Abu Abdullah. The mother of Uthman bin Affan was Arwa bint Kurayz bin Rabi'ah bin Habib bin Abd Shams, and the mother of Arwa was Umm Hakim al-Bayda' bint Abd al-Muttalib, the paternal aunt of the Messenger of Allah (peace and blessings be upon him). The mother of Umm Hakim was Fatimah bint Amr bin A'idh bin Imran bin Makhzum, who was the paternal grandmother of the Messenger of Allah (peace and blessings be upon him).
Hadith Referenceالمعجم الكبير للطبراني / العشرة / 89
Sayyiduna Ibn Abbas (may Allah be pleased with them both) said: The mother of Uthman (may Allah be pleased with him), Arwa bint Kurayz (may Allah be pleased with her), embraced Islam.
Hadith Referenceالمعجم الكبير للطبراني / العشرة / 90