Ever since the Independence Day weekend, global officials have been fighting a nettlesome Internet security problem, one that has impacted Web sites for such institutions as the Treasury Department and the Federal Trade Commission. A coordinated cyberattack on government, financial and media sites in both the U.S. and South Korea, it froze multiple sites for much of the weekend.

This afternoon, as the cyber-battle raged on, it was revealed that the list of affected institutions was longer than previously cited -- and hit closer to home for many on the Street.

The New York Stock Exchange ( NYX) and Nasdaq ( NDAQ - Get Report) -- not to mention the White House -- were reportedly also attacked.

"NYSE Euronext has been informed by authorities that its public Web site -- nyse.com -- has been the subject of a 'denial of service' cyber attack," the NYSE said in a statement. "To date, nyse.com has not experienced any impact, which may be the result of its security design. It is important to note that such an attack has not and could not impact the trading and data systems of NYSE Euronext markets, which operate on private networks. We will continue to work with authorities on this situation."

The coordinated strikes, known as denial-of-service attacks, are efforts by hackers to overwhelm and pummel Internet sites with surges in traffic. Over the weekend and through the beginning of this week, sites in South Korea and the U.S. were hit. Malicious software placed on some 20,000 computers served as the soldiers doing the dirty work.

On the South Korean side, the president's site, along with government agencies like the Ministry of National Defense, and several media and bank sites were hit.

According to a list obtained by the Associated Press, domestic targets included the State Department and the Defense Department.

Ironically, the National Security Agency and the Homeland Security Department were targeted, as well. The Washington Post was not spared, either.

Just last week, reports circulated that the Obama administration is working on finalizing a new counter-cyberattack pilot program called Einstein 3. The program has come under criticism from privacy and civil liberties advocates concerned about the NSA's role in the effort.

Recent speculation about the source of the attacks has centered on North Korea, as the Yonhap news agency in Seoul reported several unnamed South Korean officials saying as much. Still, there is no explicit evidence for the claim.

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