CVE-2021-26402

HighCVSS 7.1/10Last modified Jun 17, 2026

Description

Insufficient bounds checking in ASP (AMD Secure Processor) firmware while handling BIOS mailbox commands, may allow an attacker to write partially-controlled data out-of-bounds to SMM or SEV-ES regions which may lead to a potential loss of integrity and availability.

Metrics

CVSS 3.1 7.1/10CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H

Weakness enumeration

CWE-787

Affected software

Vendor	Product	Versions
AMD	2nd Gen EPYC	Various
AMD	3rd Gen EPYC	various

References

https://www.amd.com/en/corporate/product-security/bulletin/AMD-SB-1032Vendor Advisory
https://www.amd.com/en/corporate/product-security/bulletin/AMD-SB-1032Vendor Advisory

Timeline

Published: Jan 11, 2023
Last modified: Jun 17, 2026
NVD status: Modified

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