What’s Vulnerable › Vulnerabilities

CVE-2021-26355

• Severity: medium (CVSS 5.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2023-01-11 · updated 2026-06-17
• Weakness: CWE-693

Description

Insufficient fencing and checks in System Management Unit (SMU) may result in access to invalid message port registers that could result in a potential denial-of-service.

Affected products

• AMD Epyc 7003 Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 72F3 Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 7313 Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 7313P Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 7343 Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 7373X Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 73F3 Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 7413 Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 7443 Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 7443P Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 7453 Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 74F3 Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 7513 Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 7543 Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 7543P Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 7573X Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 75F3 Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 7643 Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 7663 Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 7713 Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 7713P Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 7743 Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 7763 Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
• AMD Epyc 7773X Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7

How to fix

Upgrade to a fixed version: AMD Epyc 7003 Firmware milanpi-sp3_1.0.0.7; AMD Epyc 72F3 Firmware milanpi-sp3_1.0.0.7; AMD Epyc 7313 Firmware milanpi-sp3_1.0.0.7; AMD Epyc 7313P Firmware milanpi-sp3_1.0.0.7; AMD Epyc 7343 Firmware milanpi-sp3_1.0.0.7; AMD Epyc 7373X Firmware milanpi-sp3_1.0.0.7; AMD Epyc 73F3 Firmware milanpi-sp3_1.0.0.7; AMD Epyc 7413 Firmware milanpi-sp3_1.0.0.7; AMD Epyc 7443 Firmware milanpi-sp3_1.0.0.7; AMD Epyc 7443P Firmware milanpi-sp3_1.0.0.7; AMD Epyc 7453 Firmware milanpi-sp3_1.0.0.7; AMD Epyc 74F3 Firmware milanpi-sp3_1.0.0.7. Check the vendor advisory for mitigations.

References

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

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