Some exceptionally popular applications have been found to be unknowingly leaking players' private details.

According to a report by the Wall Street Journal applications including Zynga's Farmville and Texas Hold 'em Poker have been inadvertently leaking player's private data and passing them on to data-mining and companies.

Both Facebook and Zynga have responded to the reports by promising to investigate and resolve the security exposed by the Wall Street Journal.

A spokesperson for Zynga said: "Zynga has a strict policy of not passing personally identifiable information to any third parties. We look forward to working with Facebook to refine how web technologies work to keep people in control of their information."

By Ewan Aiton