The inevitable happened: Intel confirms critical security issues with Intel ME: https://security-center.intel.com/advisory.aspx?intelid=INTEL-SA-00086&languageid=en-fr
"This includes scenarios where a successful attacker could: ... Load and execute arbitrary code outside the visibility of the user and operating system."
And of course it affects "6th, 7th & 8th Generation Intel® Core™ Processor Family", meaning pretty much all our desktop/laptop CPUs.