The Prophet ﷺ said, then he mentioned the lengthy hadith of the Night Journey and Ascension, in which he said,"We came to the fourth heaven.It was asked, 'Who is this?'The reply came, 'Jibreel.'It was asked, 'Who is with you?'The reply came, 'Muhammad.'It was asked, 'Has he been sent for?'The reply came, 'Yes.'It was said, 'Welcome to him. What an excellent arrival.'I then came upon Idris and greeted him, and he said, 'Welcome, dear brother and prophet.'"
قال النبي ﷺ فذكر حديث الإسراء والمعراج بطوله وجاء فيه: فأتينا السماء الرابعة قيل: من هذا؟ قيل: جبريل قيل: من معك؟ قيل: محمد قيل: وقد أرسل إليه؟ قيل: نعم قيل: مرحبا به ولنعم المجيء جاء فأتيت على إدريس فسلمت عليه فقال: مرحبا بك من أخ ونبي.
Bukhari related it in the Beginning of Creation (3207), and Muslim in Faith (264:164), both from the hadith of Saeed and Hisham, who said, "Qatada narrated to us, Anas bin Malik narrated to us from Malik bin Sasaa," and he mentioned it. Except that Muslim did not mention Hisham, but rather related it from Saeed alone, who is Ibn Abu Aruba.Tirmidhi (3157) and Ahmad (13739) both related it from Anas bin Malik himself, that Idris is in the fourth heaven. Tirmidhi said, "This is a sahih hadith. Saeed bin Abu Aruba and Hammam and more than one other related it from Qatada, from Anas, from Malik bin Sasaa, from the Prophet ﷺ, the hadith of the Ascension in full, and this, in my view, is an abridgment of that." So the hadith goes back to Malik bin Sasaa.