It is narrated from Hazrat Aisha (may Allah be pleased with her) that the Prophet (peace and blessings be upon him) used to recite Surah Al-Kafiroon and Surah Al-Ikhlas in the Sunnah prayers of Fajr. It is narrated from Hazrat Aisha (may Allah be pleased with her) that the Prophet (peace and blessings be upon him) used to recite these Surahs in a low voice in the two rak'ahs before Fajr.
Hadith Referenceمسند احمد / مسند النساء / 25510
Hadith Gradingحکم دارالسلام:حديث صحيح دون قوله: وكان رسول الله ﷺ يسير بهما وهذا إسناد منقطع وضعيف