Spectre and Meltdown aren’t anomalies. They represent a new area to look for vulnerabilities and a new avenue of attack. They’re the future of security — and it doesn’t look good for the defenders.
Modern computers do lots of things at the same time. Your computer and your phone simultaneously run several applications — or apps. Your browser has several windows open. A cloud computer runs applications for many different computers. All of those applications need to be isolated from each other. For security, one application isn’t supposed to be able to peek at what another one is doing, except in very controlled circumstances. Otherwise, a malicious advertisement on a website you’re visiting could eavesdrop on your banking details, or the cloud service purchased by some foreign intelligence organization could eavesdrop on every other cloud customer, and so on. The companies that write browsers, operating systems, and cloud infrastructure spend a lot of time making sure this isolation works.
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