The founder of the Black Hat conference has told delegates that the Secure Sockets Layer (SSL) encryption used in the majority of e-commerce is broken.
Jeff Moss was also scathing about the general state of internet security for businesses and consumers.
"Thirteen years down the line since the first conference, and we're still not able to conduct business online," he said. "SSL is broken and, while it's great to see things are going better now, it's a long way down the line."
However, security specialist Dan Kaminsky disagreed, insisting that SSL is still useful.
The situation is not perfect, according to Jane Holl Lute, US Deputy Secretary of the Department of Homeland Security (DHS), but the US government is working to sort out problems and make cyber space safe for citizens.
Lute told delegates in her keynote that securing cyber space is one of he department's key remits. "Wars end lives, but cyber space destroys them," she said.
The speed of technological advancement is such that the tools available now are almost beyond our ability to use them, Lute told delegates, although she doubted that this is true in the long term.
A comprehensive cyber security exercise will be carried out this autumn, and the DHS is gearing up for major moves to protect the online infrastructure of the US and the world, said Lute.
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