Praise be to Allaah.
The correct view is that it is permissible to wipe over khuff (leather slippers which cover the foot and ankle) or socks that have holes in them. The Prophet (peace and blessings of Allaah be upon him) allowed wiping over khuff and he did not stipulate any condition that they should be whole and free of holes or tears, especially since the khuff of his companions were not free of holes or tears. If this had any effect on whether one could wipe over them, the Prophet (peace and blessings of Allaah be upon him) would have stated that clearly, for one of the basic principles of usool al-fiqh is that it is not permitted to delay explaining something when it is needed.
Imaam Sufyaan al-Thawri (may Allaah have mercy on him) said: “One may wipe over the khuff so long as it is still clinging to the feet. Were the khuff of the Muhaajireen and Ansaar anything but full of holes and tears?” (Narrated by ‘Abd al-Razzaaq in al-Musanaaf, 1/194)
Shaykh al-Islam ibn Taymiyah (may Allaah have mercy on him) said in al-Fataawa (21/174): When the Messenger of Allaah (peace and blessings of Allaah be upon him) gave the command to wipe over the khuff, he knew what the normal state of affairs was, and he did not stipulate the condition that the socks should be whole and free of any faults. His command should be taken as general in meaning and it should not be restricted unless there is any shar’i evidence for doing so. What is implied by the wording is that any khuff that people wear and walk about in may be wiped over, even if they have holes or are worn out, without defining the acceptable extent for these holes and tears, because even such a definition would require evidence…”
This is also the view of Ishaaq, Ibn al-Mubaarak, Ibn ‘Uyaynah and Abu Thawr.
Imaam al-Shaafa'i and Ahmad – according to the well-known views narrated from them – said that it is not permissible to wipe over the khuff or socks so long as there are any holes or tears in the place where it is obligatory to do wudoo’. Abu Haneefah and Maalik differentiated between small holes and large holes.
But the correct view is the first view quoted above, which is that it is permissible to wipe over the khuff or socks so long as they are still clinging to the feet and it is still possible to walk in them.
It is also correct to wipe over socks through which the skin can be seen, because the permission to wipe over socks is general and no report of any restriction has been narrated. This implies that any socks which people wear may be wiped over. This is what is implied by those who say that it is permissible to wipe over khuff that are worn out, so long as it is still possible to walk in them.
Al-Nawawi (may Allaah have mercy on him) mentioned in al-Majmoo’ (1/502) that even if a person were to wear khuff made of glass, if it were possible to walk in them then it would be permissible to wipe over them, even though the skin beneath them would be visible…
And Allaah knows best.