You may have heard about the discovery of a major security hole affecting most recent Intel microprocessors which allows a process running on a computer to exploit a side-channel attack to read privileged information from the operating system or other processes on the same machine.
Here is the technical paper describing this exploit. This was reported by those who discovered it to the major CPU manufacturers: Intel, AMD, and ARM on 2017-06-01, but kept secret to allow time for mitigation to be put into place.
This is one of the most serious hardware problems to have discovered in mass-produced microprocessors since the notorious Intel Pentium floating point divide bug in 1994. It is difficult to exploit this bug, but it defeats the security of systems running on these processors at a fundamental level and is costly to mitigate in software, with a performance hit of up to 30% for programs which make a large number of system calls.
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