Safety instructions for AMD-SB-3005 CacheWarp

On November 14th, 2023, AMD published the Security Bulletin AMD-SB-3005. The Trusted-Computing-Technology AMD Secure Encrypted Virtualization (SEV) for EPYC processors of the generations 1 to 3, that are used for encrypting data on virtual machines, are affected. By resetting data changes in the cache, it is possible, for example, to trick the system into accepting a login as successful.

Affected systems

• systems with "Zen 1" AMD EPYC 7001 Naples processors
• systems with "Zen 2" AMD EPYC 7002 Rome processors
• systems with "Zen 3" AMD EPYC 7003 Milan processors

Solution for the problem

AMD provides for AMD EPYC 7003 processors of the "Milan B1" series the microcode update 0x0A0011D1 and for processors of the "Milan-X B2" series the microcode update 0x0A001234. We recommend to install the updated microcode via operating system.

Supermicro is working on new BIOS versions for H11 and H12 mainboards to minimize risks: Supermicro CVE-2023-20592: [1]

Updates for products of Thomas-Krenn

Updates for the corresponding system can be found in the download area of Thomas-Krenn. The updates in the download area have been tested by us to guarantee the stability and compatibility of our systems.

If you need the latest version for your system and it is not yet available in our download area, you can get it at Asus or Supermicro.

More information

• CacheWarp: Security vulnerability in all Zen 1, 2, 3 CPUs from AMD (www.heise.de, 14.11.2023)
• CacheWarp (www.cachewarpattack.com, 14.11.2023)

References

Translator: Alina Ranzinger Alina has been working at Thomas-Krenn.AG since 2024. After her training as multilingual business assistant, she got her job as assistant of the Product Management and is responsible for the translation of texts and for the organisation of the department.