Vulnerability in all AMD Zen 2 processor registers could give attackers access to sensitive information

Google Information Security has discovered an AMD processor register vulnerability (CVE-2023-20593), affecting all Zen 2 processors, allowing attackers to monitor host data in virtual machines. The vulnerability, under certain microarchitecture conditions, may prevent a register in the Zen 2 processor from being correctly written to 0, causing data from another process or thread to be stored in a YMM register, potentially allowing an attacker to access sensitive information. At present, AMD has released microcode patch updates. If the update cannot be applied, you can set "chicken bit" DE_CFG[9], but it may cause some performance loss. Affects AMD Ryzen 3000 Series, AMD Ryzen PRO 3000 Series, AMD Ryzen Threadripper 3000 Series, AMD Ryzen 4000 Series with Radeon Graphics, AMD Ryzen PRO 4000 Series, AMD Ryzen 5000 Series with Radeon Graphics, AMD Ryzen 7020 Series (with Radeon graphics processors) and AMD EPYC "Rome" series processors.