Musannaf Ibn Abi Shayba 13:1611

Abu Bakr narrated to us, he said: Abd al-A’la narrated to us, from Yunus, from al-Hasan, regarding a man who bought a slave and then emancipated him, then a disease was discovered in him that had been with the seller. He said: He [the buyer] shall hold him [the seller] liable for it, but the seller shall not return anything.