Shu'ayb narrates from his grandfather that the Messenger of Allah (peace and blessings be upon him) said: "Whichever man touches his private part, let him perform ablution, and whichever woman touches her private part, let her also perform ablution."
Muhammad bin al-Walid al-Zubaydi is thiqah (trustworthy).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الطهارة / 637
Hadith Gradingمحدثین:صحيح لغيرهٖ
Hadith Takhrij«صحيح لغيرهٖ۔ أخرجه الدار قطني 1/147»