Sahih Muslim , Hadith 261 ⓘ
'A'isha reported: The Messenger of Allah said: Ten are the acts according to fitra: clipping the moustache, letting the beard grow, using the tooth-stick, snuffing water in the nose, cutting the nails, washing the finger joints, plucking the hair under the armpits, shaving the pubes and cleaning one's private parts with water. The narrator said: I have forgotten the tenth, but it may have been rinsing the mouth.
حَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، وَأَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ وَزُهَيْرُ بْنُ حَرْبٍ قَالُوا حَدَّثَنَا وَكِيعٌ، عَنْ زَكَرِيَّاءَ بْنِ أَبِي زَائِدَةَ، عَنْ مُصْعَبِ بْنِ شَيْبَةَ، عَنْ طَلْقِ بْنِ حَبِيبٍ، عَنْ عَبْدِ اللَّهِ بْنِ الزُّبَيْرِ، عَنْ عَائِشَةَ، قَالَتْ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " عَشْرٌ مِنَ الْفِطْرَةِ قَصُّ الشَّارِبِ وَإِعْفَاءُ اللِّحْيَةِ وَالسِّوَاكُ وَاسْتِنْشَاقُ الْمَاءِ وَقَصُّ الأَظْفَارِ وَغَسْلُ الْبَرَاجِمِ وَنَتْفُ الإِبْطِ وَحَلْقُ الْعَانَةِ وَانْتِقَاصُ الْمَاءِ " . قَالَ زَكَرِيَّاءُ قَالَ مُصْعَبٌ وَنَسِيتُ الْعَاشِرَةَ إِلاَّ أَنْ تَكُونَ الْمَضْمَضَةَ . زَادَ قُتَيْبَةُ قَالَ وَكِيعٌ انْتِقَاصُ الْمَاءِ يَعْنِي الاِسْتِنْجَاءَ .
also referenced under: Book 2, Hadith 71 (In-Book) & Book 2, Hadith 502 (USC-MSA)
This hadith has been narrated by Mus'ab b. Shaiba with the same chain of transmitters except for these words: " His father said: I forgot the tenth one."
وَحَدَّثَنَاهُ أَبُو كُرَيْبٍ، أَخْبَرَنَا ابْنُ أَبِي زَائِدَةَ، عَنْ أَبِيهِ، عَنْ مُصْعَبِ بْنِ شَيْبَةَ، فِي هَذَا الإِسْنَادِ مِثْلَهُ غَيْرَ أَنَّهُ قَالَ قَالَ أَبُوهُ وَنَسِيتُ الْعَاشِرَةَ .
also referenced under: Book 2, Hadith 72 (In-Book) & Book 2, Hadith 503 (USC-MSA)