Sayyiduna Abu Mas'ud al-Ansari (may Allah be pleased with him) said: The Prophet (peace and blessings be upon him) became thirsty near the Ka'bah, and nabidh was brought to him (peace and blessings be upon him). He (peace and blessings be upon him) made a face at its smell, called for Zamzam water and poured it into it, then drank it. A man said: O Messenger of Allah, is it unlawful? He (peace and blessings be upon him) said: "No." In one narration, he (peace and blessings be upon him) was asked: Is this lawful or unlawful? And he (peace and blessings be upon him) said: "Lawful."
Ali bin Umar (al-Daraqutni) said: This hadith is known through Yahya bin Yaman; it is said that the chain got switched for him and mixed up with the hadith of al-Kalbi from Abu Salih. Al-Kalbi is matruk (abandoned), and Abu Salih is da'if (weak).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الأشربة والحد فيها / 17438