Is Touching the Ka`bah Sunnah?
Question

During tawaf we see some people touching the walls and covering of the Ka`bah, and Maqam Ibrahim. What is the ruling on that?
Praise be to Allah.This question was put to Shaykh Muhammad ibn ‘Uthaymin (may Allah have mercy on him), who replied as follows: 
Did the Prophet touch the Ka`bah?
“Touching the Ka`bah is an action which some people do, seeking thereby to draw closer to Allah and to worship Him. Every action which is done with the intention of drawing closer to Allah and worshipping Him, but which has no basis in the Shari`ah, is an innovation. The Prophet (peace and blessings of Allah be upon him) warned against that when he said: “Beware of newly-innovated matters, for every innovation is a going astray.” (Narrated by al-Tirmidhi, 2676; Abu Dawud, 4607)
It is not narrated that the Prophet (peace and blessings of Allah be upon him) touched anything apart from the Yemeni Corner and the Black Stone. 
On this basis, if a person touches any corner or side of the Ka`bah apart from the Yemeni Corner and the Black Stone , then he is considered to be an innovator (follower of bid’ah).
When ‘Abd-Allah ibn `Abbas saw Mu’awiyah ibn Abi Sufyan (may Allah be pleased with him) touching the two northern corners of the Ka`bah, he told him not to do that. Mu’awiyah (may Allah be pleased with him) said to him: “No part of the House should be ignored.’ Ibn `Abbas (may Allah be pleased with him) said: “ ‘Indeed in the Messenger of Allah (Muhammad) you have a good example to follow” [al-Ahzab 33:21 – interpretation of the meaning]. And I saw the Prophet (peace and blessings of Allah be upon him) touching the two Yemeni corners,” meaning the Yemeni Corner and the Black Stone. So Mu’awiyah accepted what Ibn `Abbas said. 
Did the Prophet touch Maqam Ibrahim?
A more serious form of bid`ah is what some people do, namely touching Maqam Ibrahim . It was not narrated that the Prophet (peace and blessings of Allah be upon him) touched any part of the Maqam .
Did the Prophet touch Zamzam?
The same applies to other actions that some people do, namely touching Zamzam or touching the pillars of the porticos – the ancient pillars built by the Ottomans. None of these actions were narrated from the Prophet (peace and blessings of Allah be upon him), so they are all bid`ah (innovations), and every innovation is a going astray.”
And Allah knows best.