Ayesha reported,

She informed him that whenever the muadhdhin finished the call to prayer for the dawn prayer and the morning light appeared, the Messenger of Allah ﷺ would pray two brief units of prayer before the iqamah was called.

Muslim 1676

Sahih

حدثنا يحيى بن يحيى قال قرأت على مالك عن نافع عن ابن عمر أن

حفصة أم المؤمنين

أخبرته أن رسول الله ﷺ كان إذا سكت المؤذن من الأذان لصلاة الصبح وبدا الصبح ركع ركعتين خفيفتين قبل أن تقام الصلاة

مسلم 1676صحيح
Contents
Reference
Commentary
Ayat
Collection
Sahih Muslim
Book
Travelers' prayer and its shortening
Chapter
Recommendation of the two Fajr sunnah rakahs, encouragement to perform them, making them light, being consistent with them, and what is recommended to recite in them
Numbering
Darussalam 1676
Muslim 1676