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Several recently-published research articles have demonstrated a new class of timing attacks (Meltdown and Spectre) that work on most modern CPUs. The sky is not falling but this should be taken seriously and unfortunately will require an active response that may shift priorities.
At best, the vulnerability could be leveraged by malware and hackers to more easily exploit other security bugs. At worst, the hole could be abused by programs and logged-in users to read the contents of the kernel's memory. It affects operating systems and can leverage web browsers to attack.
Reduced performance on Intel-based Microsoft Windows, MacOS, or Linux servers may be experienced as the operating systems are patched to close the security hole. One projections puts this at a performance reduction between 17% and 23%.
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