The company stated the following on their official Facebook page:
On Wednesday, Aug. 15, 2012, an official at Saudi Aramco confirmed that the company has isolated all its electronic systems from outside access as an early precautionary measure that was taken following a sudden disruption that affected some of the sectors of its electronic network.
The disruption was suspected to be the result of a virus that had infected personal workstations without affecting the primary components of the network. Saudi Aramco confirmed the integrity of its electronic network that manages its core business and that the interruption has had no impact whatsoever on any of the company’s production operations.
The company employs a series of precautionary procedures and multiple redundant systems within its advanced and complex system that are used to protect its operational and database systems.
According to some unconfirmed reports via Twitter and Pastebin, the situation is much more serious.
These type of information should be taken with a grain of salt, but it said that a large number of systems were completely wiped and that both web and mail servers, as well as the domain controller were also hit in the attack.