Sunan Abu Dawud
2079
Daif+2

Ibn ‘Umar reported the Prophet (ﷺ) as saying “If a slave marries without the permission of his master, his marriage is null and void. Abu Dawud said “This tradition is weak. This is mauquf(does not go back to the Prophet). This is the statement of the Ibn ‘Umar himself

DaifAl-Albani
DaifMuhammad Muhyi Al-Din Abdul Hamid