Al-Hakam and Talhah bin Musarrif narrated: Sayyiduna Ma'qil bin Sinan (may Allah be pleased with him) came to Sayyiduna Abdullah (may Allah be pleased with him) and asked him about a man who makes a vow but does not specify anything. Sayyiduna Abdullah (may Allah be pleased with him) said: "He should free a slave."
Imam al-Tabarani recorded it in al-Mu'jam al-Kabir, and its narrators are the narrators of the Sahih, except that Talhah and al-Hakam did not hear from Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him).