Honestly, right now I see it difficult, with the amount of UCL that Real Madrid has right now and the team they have, I see it difficult for a team to surpass Real Madrid in the short term, the closest one is Milan with 7 Champions League, and right now in level, it is very far from Real Madrid.
It might take the next hundred years for a team to overtake the champions league trophy haul of Real Madrid. The champions league is getting more difficult for a team to even win twice in five years as the years roll by.