According to Graham Cluley, senior technology consultant with Sophos, the reason for the crash was a central computer system (used to monitor the plane's IT systems for problems) being infected by malware.

A report in Spanish newspaper El Pais cites an internal report by Spanair that a computer system located at the airline's headquarters should have spotted three similar issues with the plane's systems, but was hit by malware.

According to the newspaper, says Cluley, the plane should not have been allowed to take-off if the technical problems had been identified. But, the Sophos senior technology consultant stresses: "It's important to note - malware didn't cause the plane to crash."

"The US National Transportation Safety Board, for instance, reported in a preliminary investigation that the plane had taken off with its flaps and slats retracted - and that no audible alarm had been heard to warn of this because the systems delivering power to the take-off warning system (TOWS) failed", he said in his security blog.

"If the news story is accurate, however, malware may have affected computer systems that (if they had been working properly without interference) would have meant the flight might never have attempted to take off in the first place", he added.

Cluley notes that, "unfortunately we don't know the name of the malware that is under suspicion in this case, so it's tricky to comment further."

He also adds the sanguine observation: "Next time someone tries to convince you that the people who write malware aren't really doing anyone any serious harm - remember this case."