This allegation has been found on Catholic websites, not in writings from the Vatican.
The implication here is that being a Mason opens doors, gives social contacts and can thus be profitable for businessmen and useful for those who seek employment, because Masons give each other preferential treatment, to the detriment of others.
I have myself never seen any such thing, except that Masons sometimes receive such things as a 10% rebate in shops owned by Masons -- which is not stranger than that shops sometimes give rebates to members of sports clubs or other associations.
There have been many allegations of "brother-corruption" among Masons in e.g. British law enforcement and in French local politics. Yet I have never seen evidence of an actual case where there was a clear connection to Freemasonry -- just allegations, which often seem to be based on "popular paranoia" rather than relevant facts. This paranoia is understandable, in a way. People will notice that many leading members of their community are Freemasons, and when one does not know what Freemasonry is about, one's imagination will fill in the rest. Small wonder that Freemasons have often identified themselves with the Knights Templars, who were the victims of precisely this sort of suspicious thinking.
The type of corruption we are talking about here is certainly a risk in any closed association of people, but it seems to me that the frequency of occurrences depends mostly on social structures and traditions in a culture. For instance, bribery is more or less an accepted standard behaviour in parts of Africa and Asia. Sicily gave birth to the mafia. Soviet communism caused the appearance of a huge black market and subsequently the Russian mafia. There are also professions where you easily develop an "esprit du corps", e.g. the police and the military, which may lead to the same sort of conspiracies in order to protect other members of the corps. I do not deny that there exists a risk for this type of behaviour in Freemasonry, but it is no greater here than in hundreds of other places.
Anti-masons will reply that there is a special risk with Freemasonry because the brethren are bound to each other by oaths. This is simply not true. There is nothing in the Masonic oaths which requires or even admonishes Freemasons to give unfair preferential treatment to each other. Quite the contrary, using the fraternity to gain unfair advantages is generally regarded by Masons as a shameful thing. Those who join Freemasonry for personal gain -- and they do exist -- are usually very disappointed.