A bug in Intel Skylake processors has been discovered by the hardwareluxx.de community and passed onto mathematicians at Great Internet Mersenne Prime Search (GIMPS), who have tested and confirmed it with Intel.
"Intel has identified an issue that potentially affects the 6th Gen Intel Core family of products," they say. "This issue only occurs under certain complex workload conditions, like those that may be encountered when running applications like Prime95. In those cases, the processor may hang or cause unpredictable system behaviour."
It's expected that only stress testing and operations conducted at scientific and financial institutions would trigger the bug.
In any case, a fix is on the way and should distributed through Intel's hardware partners via a BIOS update soon.