I say: Its narrators are reliable, except for Ufair ibn Ma'dan, who is weak, as stated in al-Taqrib. Al-Haythami likewise identified him as its defect in al-Majma' (7/326).

I also say: Ma'mar narrated it from Qatadah, from al-Hasan, as a mursal report. Abd al-Razzaq recorded it in al-Musannaf (11/374/20780). Thus, the defect lies in al-Hasan's use of the ambiguous transmission formula “from”—and he was al-Hasan al-Basri. Given the scholars' disagreement over whether he heard from Samurah, and since some of them accused him of concealment in transmission, while he narrates it with this ambiguous formula, as you can see, it is possible that he received it from Tha'labah ibn 'Ibad al-'Abdi al-Basri. Indeed, al-Aswad ibn Qays narrated it from Tha'labah, who said:

“One day, I attended a sermon delivered by Samurah ibn Jundub. In his sermon, he related a hadith from the Messenger of Allah, peace and blessings be upon him, and said…”

I say: He then mentioned the Prophet's eclipse prayer and the sermon he delivered afterward, which included:

“By Allah, the Hour will not come until thirty liars emerge, the last of whom will be the one-eyed Dajjal … That will not happen until you see matters whose gravity grows in your minds, and you ask one another, ‘Did your Prophet ever tell you anything about them?’ and until mountains are removed from their places. Then, in the wake of that, there will be the taking of souls.”

Ahmad, al-Tabarani (7/225–231), and some of the compilers of the Sunan collections recorded it. Ibn Khuzaymah (2/325/1397), Ibn Hibban (nos. 2852 and 2856 in al-Ihsan), and al-Hakim (1/329) authenticated it.

Its narrators are reliable, except for this Tha'labah: no one declared him reliable except Ibn Hibban (4/98), and no one narrated from him other than this al-Aswad. This report is cited in Da'if Abi Dawud (216).