The denial of service attack that disrupted the Wells Fargo & Co. electronic banking operations Tuesday was the fourth since last week. And it appears to lend some credence to threats and claims that the Izz al-Din al-Qassam Cyber Fighters, the military wing of Hamas, the Islamic party that governs the Gaza Strip, are behind them.
The group claimed responsibility for DoS attacks against Bank of America, JPMorgan Chase and Citigroup Inc. that disrupted online operations, and said the attacks would continue "until the Erasing of that nasty movie" -- a reference to a trailer of the independent film "Innocence of Muslims," which Muslims say insults the Prophet Muhammed.
This week, it said it had conducted Tuesday's Wells Fargo attack and that its next targets would be U.S. Bancorp and PNC Financial Services. Reports surfaced on Wednesday saying customers of those two institutions were having trouble accessing their websites.
Since the attacks began, there have been multiple theories floated about the source.
U.S. Sen. Joseph Lieberman (I-Conn), chairman of the Senate Homeland Security Committee, said last week in an interview on C-SPAN's "Newsmakers" program that he believed a unit of Iran's Revolutionary Guard Corps was behind them.
Also last week, the FBI issued a fraud alert, warning financial services firms that cybercriminals might try to disrupt their websites in an effort to distract them from noticing fraudulent wire transfers.
Some security experts said at the time that they might not even be attacks, but simply internal technical problems, similar to what shut down GoDaddy recently. Or, that they might simply be low-level attacks by anti-capitalist groups with a political agenda.
And even now there is not unanimous agreement that Izz al-Din al-Qassam Cyber Fighters is behind all the attacks. The group has not made good on all of its threats. It had also said it would attack the New York Stock Exchange, but trading has continued normally there.
Dmitri Alperovitch, chief executive of CrowdStrike, a private security firm investigating the attacks, told the Los Angeles Times that the claims "appear to be accurate in terms of predicting future attacks. But I wouldn't necessarily take at face value any of its claims about attribution or the video."
Whatever their source, the attacks have prompted some renewed calls for more coordination between the private sector and government, which was the goal of the 2012 Cyber Security Act (CSA) that failed in Congress last month.
But so far, they have not been even close to catastrophic, partially because, as a number of security experts have noted, DoS attacks are among the oldest and most basic, and do not require highly skilled computer programmers or advanced expertise.
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