Ubaydullah bin Abdullah (may Allah have mercy on him) narrates from Sayyiduna Umar bin al-Khattab (may Allah be pleased with him) that Sayyiduna Umar (may Allah be pleased with him) asked Abu Waqid al-Laythi (may Allah be pleased with him): What did the Messenger of Allah (peace and blessings be upon him) recite in the two Eids? He said: He (peace and blessings be upon him) used to recite "Qaf. By the glorious Qur'an [Surah Qaf: 1] and The Hour has drawn near and the moon has split [Surah al-Qamar: 1]."
Al-Shafi'i said in the narration of Harmalah: This is established if Ubaydullah met Abu Waqid al-Laythi. The Shaykh said: This is because Ubaydullah did not reach the days of Umar and his questioning of him; because of this defect al-Bukhari left this hadith out of the Sahih, while Muslim recorded it, because Fulayh bin Sulayman narrated it from Damrah, from Ubaydullah, from Abu Waqid, who said: Umar (may Allah be pleased with him) asked me; so the hadith thereby became connected (mawsul).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب صلاة العيدين / 6191