Sayyiduna Ali (may Allah be pleased with him), Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) and Sayyidah Aishah (may Allah be pleased with her) said: "When the private part passes the private part, the ritual bath (ghusl) becomes obligatory." Its chain contains Jabir al-Ju'fi, who is da'if (weak).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الطهارة / 1444