Intel's latest financial filing with the Securities and Exchange Commission reveals that the company was targeted in a sophisticated hacking attack in January, a risk not previously cited in the company's quarterly filings.

"One recent and sophisticated incident occurred in January 2010 around the same time as the recently publicized security incident reported by Google," the company states in its Form 10-K Annual Report. "We seek to detect and investigate these security incidents and to prevent their recurrence, but in some cases we might be unaware of an incident or its magnitude and effects."

Such attacks, the company says, "are sometimes successful."

The chip-making giant says that it regularly faces attempts to penetrate its systems, which may represent industrial espionage or efforts to harm the company.

Intel did not respond to requests for comment about the impact of the successful attacks.

It's not clear how alarmed organizations should be by such attacks, given that Intel's acknowledgment comes as a matter of regulatory compliance. Financial filings typically cite worst-case scenarios to protect companies from liability.

Google in January said that it had detected "a highly sophisticated and targeted attack on our corporate infrastructure originating from China that resulted in the theft of intellectual property" and declared it would alter its cooperation with Chinese censors as a consequence.

Google's statement, in conjunction with news that some 33 other companies had been targeted in what security researchers dubbed "Operation Aurora," prompted significant concern from the U.S State Department.

The subsequent finding that over 74,000 personal, corporate and government computers at over 2,500 organizations around the world had been compromised by Trojan malware and turned into bots led Amit Yoran, former DHS cybersecurity director and the current CEO of security vendor NetWitness, to state, "These large-scale compromises of enterprise networks have reached epidemic levels."

Yet, this ostensible epidemic doesn't alarm everyone. In response to Google's revelation, Microsoft CEO Steve Ballmer told Reuters, "We're attacked every day from all parts of the world and I think everybody else is too. We didn't see anything out of the ordinary."

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