Are the hadiths narrated regarding the Mahdi sound or weak?

Authentic hadiths have been successively narrated from the Prophet, peace and blessings be upon him, regarding the appearance of the Mahdi at the end of time. He is said to be from the Prophet's household, his name will coincide with the Prophet's name, and his father's name will coincide with the Prophet's father's name. He will fill the earth with justice and fairness after it has been filled with tyranny and injustice. He will rule for seven years, and Jesus, peace be upon him, will pray behind him. The imams and scholars have affirmed the successive narration (tawatur) of these hadiths with a spiritual tawatur, emphasizing that belief in the advent of the Mahdi is obligatory for the Ahl al-Sunnah wal-Jama'ah, and that the attempts of deceivers to claim Mahdism do not harm the belief of the Ahl al-Sunnah.