CVE-2021-26339

MediumCVSS 5.5/10Last modified Jun 17, 2026

Description

A bug in AMD CPU’s core logic may allow for an attacker, using specific code from an unprivileged VM, to trigger a CPU core hang resulting in a potential denial of service. AMD believes the specific code includes a specific x86 instruction sequence that would not be generated by compilers.

Metrics

CVSS 3.1 5.5/10CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected software

Vendor	Product	Versions
AMD	EPYC™ Processors	various
AMD	Ryzen™ Series	various
AMD	Athlon™ Series	various

References

https://www.amd.com/en/corporate/product-security/bulletin/amd-sb-1027Vendor Advisory
https://www.amd.com/en/corporate/product-security/bulletin/amd-sb-1028Vendor Advisory
https://www.amd.com/en/corporate/product-security/bulletin/amd-sb-1027Vendor Advisory
https://www.amd.com/en/corporate/product-security/bulletin/amd-sb-1028Vendor Advisory

Timeline

Published: May 11, 2022
Last modified: Jun 17, 2026
NVD status: Modified

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