The destructive ‘Shamoon’ malware attacks hit the Saudi Arabian Aramco oil company last month could have been aided by a rogue insider, a source has told Reuters news agency.

Activating on 15 August, Shamoon (also known as ‘Disttrack’) set about wiping parts of the master boot record (MBR) on the hard drive of any Windows system it could reach, a technique designed to cause chaos on target networks.

In the case of Aramco, Saudi Arabia’s national oil producer, it succeeded in this ambition, reportedly damaging 30,000 systems.

A group calling itself the ‘Cutting Sword of Justice’ claimed responsibility for the attack, which many assumed marked the incident as being pro-Iranian in its origins although Syria and the political upheaval on Bahrain are also seen as possible motivations.

According to Reuters, Aramco has hired security forms to work out how the malware got inside its defences with one hypothesis being that it was either introduced internally or using information supplied from an internal source.

"It was someone who had inside knowledge and inside privileges within the company," reuters quoted the source as saying.

Although external targeted attacks are not hard to pull off, the huge scale and rapidity of the Shamoon attacks suggests that it had some sense of the layout of the internal LANs it was trying to target.

Fast-spreading attacks are invariably the work of worms but these can be slowed by today’s security systems. For some reason Shamoon was able to bypass this layer of control which hints that it was more coordinated that an old-fashioned worm.

As the largest oil production company in the world in the largest oil producing state, Saudi Arabia, Aramco is no ordinary target. Anyone attacking it would be doing so with commercial or political intent.

By odd coincidence, Shamoon was not the only example of data-wiping malware to target the oil industry in the Middle East this year, following on the heels of an even more mysterious attack dubbed ‘Wiper’.

Recently analysed by Kaspersky Lab, this hit computers in Iran in April, causing significant damage to the company’s oil industry using the same hard drive-wiping technique.

Iran itself has said little about the nature of the attacks but Kaspersky Lab has been able to link them using rather sketchy forensic evidence to prominent attacks such as Stuxnet, Flame, Gauss and Duqu. That would make them a part of a larger and longer-term cyberattack campaign meant to harm Iran, in this case possibly by deleting an evidence trail connected to a previous attack.

Might the Shamoon attacks be some kind of retaliation emanating from Iran, targeting the same industry sector using less sophisticated but still effective technology? For now nobody knows but the message is clear – major oil producers will have to guard against no-holds barred attacks from now on.