That's according to a report in the Sunday Times with an unnamed source telling the newspaper, "Everything Sony purchased from the Michael Jackson estate was compromised. It caused them to check their systems and they found the breach. There was a degree of sophistication. Sony identified the weakness and plugged the gap."

Sony purchased the catalogue in 2010 from the Jackson estate for $250 million (?164m) gaining the right to sell said back-catalogue and unreleased tracks.

Although the incident has ...