On the authority of Abu Hurayrah, who said: The Messenger of Allah, peace and blessings be upon him, said: "Five things are from the fitrah: circumcision, shaving the pubic hair, plucking the armpit hair, trimming the nails, and trimming the mustache."(1)

Malik's stopping of it (as a statement of Abu Hurayrah, not of the Prophet):

5044 - Qutaybah informed us, from Malik, from al-Maqburi, from Abu Hurayrah, who said: "Five things are from the fitrah: trimming the nails, trimming the mustache, plucking the armpit hair, shaving the pubic hair, and circumcision."(2)

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(1) A sound hadith. His saying "and plucking the armpit hair" (wa natf al-dab') is unique to 'Abd al-Rahman ibn Ishaq—who is al-Madani—and he is truthful. The reliable narrators have narrated it with the wording "and plucking the armpit hair" (wa natf al-ibt), as has preceded under number (9). The armpit is also called al-dab', as will come later, so he may have narrated it by meaning. Bishr: he is Ibn al-Mufaddal, and it is in al-Sunan al-Kubra under number (9244).

Al-Bukhari also narrated it in al-Adab al-Mufrad (1293), and al-Bazzar (8467) via the route of Yazid ibn Zuray', from 'Abd al-Rahman ibn Ishaq, with this chain of transmission. However, it came in al-Bazzar on the standard path with the wording: "and plucking the armpit hair" (wa natf al-ibt). And Allah knows best.

Al-Daraqutni cited the narration (without citing its text) in al-'Ilal 8/142.

Ibn al-Athir said in al-Nihayah (dab'): The armpit is called al-dab' due to adjacency. Al-Fayruzabadi said in al-Qamus: al-dab' is the entire upper arm, or its middle with its flesh, or the armpit, or what is between the armpit to half of the upper arm from its top.

(2) A sound hadith. Malik stopped it (as a statement of Abu Hurayrah), and the narrators from him in al-Muwatta' did not differ regarding the stopping of this hadith, as Ibn 'Abd al-Barr mentioned in al-Istidhkar 26/240. Qutaybah: he is Ibn Sa'id, and al-Maqburi: he is Sa'id ibn Abi Sa'id. It is in al-Sunan al-Kubra under number (9245).

It has preceded as raised (to the Prophet) in the hadith before it, and under numbers (9), (10), and (11), and it is the preserved version from the hadith of Abu Hurayrah, as Ibn 'Abd al-Barr mentioned.

There has been disagreement regarding Malik concerning the mention of Abu Sa'id al-Maqburi in its chain of transmission:

Qutaybah ibn Sa'id narrated it—as in this narration—from Malik, from Sa'id al-Maqburi, from Abu Hurayrah as his statement. So he did not mention Abu Sa'id al-Maqburi in his chain of transmission. =