Mar 31, 2011 07:46 GMT  ·  By

The recent hacking attack at NASDAQ, the world's second-largest stock trading market, might have been more serious than originally thought as the National Security Agency was brought into the investigation.

Joel Brenner, the former head of U.S. counterintelligence, told Bloomberg that the involvement of NSA in the investigation suggests a state sponsored attack or very capable hackers.

It could also suggest a need of NSA special capabilities the FBI lacks, such as advanced computing power and data decryption skills.

The NASDAQ security breach was disclosed last month, but a company spokesman said at the time that the stock trading platform was not affected.

Instead, the hackers targeted Directors Desk, a Web platform used by Nasdaq OMX's corporate customers to exchange private information that could prove valuable.

According to Bloomberg's sources, the attack might have been more widespread than initially thought and the focus of the investigation is to determine how far the hackers reached.

NSA's involvement is most likely also tied to NASDAQ's national importance, as the agency doesn't usually participate to investigations that concern cyber attacks against private companies.

The only other case when NSA got officially involved was in 2009 when hackers managed to break into computers at Google and at least 30 other Fortune 500 companies.

Sophisticated attackers can siphon out data in encrypted form in order to prevent investigators from determining their target and begin risk mitigation. If that's what happened in this case, then NSA's skill set might prove extremely valuable.

There are also voices that say the incident might restrict the company's ability to apply its strategies. At the very least, the breach is sure to have investors concerned.

The origin of the attack is currently unknown. There were previous signs that pointed to Russia, but that proved to be an incorrect assessment.