Prof. Danny Dolev of the Cyber Research Center at Hebrew University told Arutz Sheva Thursday that he doubts the veracity of official explanations for power outages and website crashes Wednesday at the New York Stock Exchange, the Wall Street Journal, and United Airlines.
"The event at the New York Stock Exchange is not clear," he said. The official claim, that it has to do with a recent software or system update, "may be the reason," he said, but he added: "Three different major events occurred yesterday in the US. The chance of three different major events happening on the same day within a few hours of each other is very slim."
The events could be a terrorist attack or a cyber attack, he said. the term "terror attack" is used with regard to action by an individual or a small group, he explained, while action by a state-sized entity is called a cyber-attack.
In the near future, he predicted, much tougher measures will be taken regarding access to protected sites.
The New York Stock Exchange shut down trading on Wednesday at exactly 11:32 a.m. local time and did not resume until 3:10 p.m.
In a brief announcement, the exchange said it was experiencing an "internal technical issue." Later, NYSE stressed in a tweet that the suspension was "not the result of a cyber breach."
Similar technical malfunctions also occurred earlier Wednesday morning at United Airlines, as well as to the homepage of The Wall Street Journal at roughly the same time as the NYSE.
The Journal managed to restore a limited homepage by 12:18 p.m. along with the message "WSJ.com is having technical difficulties. The full site will return shortly."
United Airlines's computer system was up and running by the time the NYSE and the Journal shut down.
The Department of Homeland Security told CNN that there is "no sign of malicious activity" at the NYSE or United Airlines. The Federal Bureau of Investigation has contacted the NYSE and "no further law enforcement action is needed at this time."
US Secretary of Homeland Security Jeh Johnson confirmed the technical glitches were not the result of hostile action, but noted that President Barack Obama was requesting all possible updates.