Reference: al-Bid’u wal-Muhdathaat wa maa laa Asla lahu – Page 388
Fiqh al-‘Ibaadaat – Page 348
Question: Is it permissible to kiss the Yemeni corner [of the Ka’bah]?
Response: Kissing the Yemeni corner (ar-Rukn al-Yamanee) is not confirmed from the Messenger of Allaah ﷺ. Any act of worship which is not confirmed from the Messenger of Allaah ﷺ is an innovation and not something which draws one near to Allaah. So based upon this, it is not legislated for a person to kiss the Yemeni corner since this is not confirmed upon the Prophet ﷺ. Rather, it has been mentioned in a weak hadeeth that can not be used as proof.