What is CVE-2021-26327?

CVE-2021-26327 is a medium-severity vulnerability in AMD 3rd Gen Epyc™, classified under Improper Input Validation. CVSS score: 5.5/10. Published 2021-11-16.

How severe is CVE-2021-26327?

Medium severity. CVSS v3 base score is 5.5 out of 10.

Improper input validation in AMD 3rd Gen Epyc™

CVE-2021-26327

Insufficient validation of guest context in the SNP Firmware could lead to a potential loss of guest confidentiality.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

Published 2021-11-16 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.002 (13.6th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 14th percentile — 13.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000

Affected products

AMD 3rd Gen Epyc™ — versions unspecified
AMD Epyc 7003
AMD Epyc 7003 Firmware
AMD Epyc 72f3
AMD Epyc 72f3 Firmware
AMD Epyc 7313
AMD Epyc 7313 Firmware
AMD Epyc 7313p
AMD Epyc 7313p Firmware
AMD Epyc 7343

Weakness classification (CWE)

References

www.amd.com/en/corporate/product-security/bulletin/amd-sb-1021 (Vendor Advisory)

Frequently asked questions

What is CVE-2021-26327?: CVE-2021-26327 is a medium-severity vulnerability in AMD 3rd Gen Epyc™, classified under Improper Input Validation. CVSS score: 5.5/10. Published 2021-11-16.
How severe is CVE-2021-26327?: Medium severity. CVSS v3 base score is 5.5 out of 10.