Researchers at a cyber-security consulting company in Israel have claimed that they have found 13 serious vulnerabilities in AMD processors. CTS-Labs has published details about the flaws, which have been given names such as Masterkey, Ryzenfall, Fallout, and Chimera. However, the research company has faced criticism for not giving AMD sufficient time or forewarning to work on fixes for the security issues.
https://www.notebookcheck.net/Serious-security-flaws-discovered-in-AMD-chips.289142.0.html