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Vulnerability record · CVE-2021-26340 · published 10 December 2021

CVE-2021-26340: Amd epyc 7001 firmware vulnerability

AAmd · Epyc 7001 Firmware

A malicious hypervisor in conjunction with an unprivileged attacker process inside an SEV/SEV-ES guest VM may fail to flush the Translation Lookaside Buffer (TLB) resulting in unexpected behavior inside the virtual machine (VM).

8.4 CVSS 3.1 High EPSS 0.24% · top 86.5%
8.4CVSS 3.1 base score, v2 3.6
0.24%EPSS exploitation probability, 30 days
NoNot in CISA KEV
105Affected product versions listed by NVD
2References
17 Jun 2026Last modified by NVD

Description

A malicious hypervisor in conjunction with an unprivileged attacker process inside an SEV/SEV-ES guest VM may fail to flush the Translation Lookaside Buffer (TLB) resulting in unexpected behavior inside the virtual machine (VM).

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

Affected products

105 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://www.amd.com/en/corporate/product-security/bulletin/amd-sb-1023 Vendor Advisory
https://www.amd.com/en/corporate/product-security/bulletin/amd-sb-1023 Vendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2021-26340), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.