CVE-2021-26364

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: 2022-05-11 · updated 2026-06-17
Weakness: CWE-119

Description

Insufficient bounds checking in an SMU mailbox register could allow an attacker to potentially read outside of the SRAM address range which could result in an exception handling leading to a potential denial of service.

Affected products

AMD Epyc 7232P Firmware: before romepi-sp3_1.0.0.d — fixed in romepi-sp3_1.0.0.d
AMD Epyc 7252 Firmware: before romepi-sp3_1.0.0.d — fixed in romepi-sp3_1.0.0.d
AMD Epyc 7262 Firmware: before romepi-sp3_1.0.0.d — fixed in romepi-sp3_1.0.0.d
AMD Epyc 7272 Firmware: before romepi-sp3_1.0.0.d — fixed in romepi-sp3_1.0.0.d
AMD Epyc 7282 Firmware: before romepi-sp3_1.0.0.d — fixed in romepi-sp3_1.0.0.d
AMD Epyc 72F3 Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
AMD Epyc 7302 Firmware: before romepi-sp3_1.0.0.d — fixed in romepi-sp3_1.0.0.d
AMD Epyc 7302P Firmware: before romepi-sp3_1.0.0.d — fixed in romepi-sp3_1.0.0.d
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 7352 Firmware: before romepi-sp3_1.0.0.d — fixed in romepi-sp3_1.0.0.d
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 7402 Firmware: before romepi-sp3_1.0.0.d — fixed in romepi-sp3_1.0.0.d
AMD Epyc 7402P Firmware: before romepi-sp3_1.0.0.d — fixed in romepi-sp3_1.0.0.d
AMD Epyc 7413 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 7452 Firmware: before romepi-sp3_1.0.0.d — fixed in romepi-sp3_1.0.0.d
AMD Epyc 7453 Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
AMD Epyc 7473X 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 7502 Firmware: before romepi-sp3_1.0.0.d — fixed in romepi-sp3_1.0.0.d
AMD Epyc 7502P Firmware: before romepi-sp3_1.0.0.d — fixed in romepi-sp3_1.0.0.d
AMD Epyc 7513 Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
AMD Epyc 7532 Firmware: before romepi-sp3_1.0.0.d — fixed in romepi-sp3_1.0.0.d
AMD Epyc 7542 Firmware: before romepi-sp3_1.0.0.d — fixed in romepi-sp3_1.0.0.d
AMD Epyc 7543P Firmware: before milanpi-sp3_1.0.0.7 — fixed in milanpi-sp3_1.0.0.7
AMD Epyc 7552 Firmware: before romepi-sp3_1.0.0.d — fixed in romepi-sp3_1.0.0.d
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

How to fix

Upgrade to a fixed version: AMD Epyc 7232P Firmware romepi-sp3_1.0.0.d; AMD Epyc 7252 Firmware romepi-sp3_1.0.0.d; AMD Epyc 7262 Firmware romepi-sp3_1.0.0.d; AMD Epyc 7272 Firmware romepi-sp3_1.0.0.d; AMD Epyc 7282 Firmware romepi-sp3_1.0.0.d; AMD Epyc 72F3 Firmware milanpi-sp3_1.0.0.7; AMD Epyc 7302 Firmware romepi-sp3_1.0.0.d; AMD Epyc 7302P Firmware romepi-sp3_1.0.0.d; AMD Epyc 7313P Firmware milanpi-sp3_1.0.0.7; AMD Epyc 7343 Firmware milanpi-sp3_1.0.0.7; AMD Epyc 7352 Firmware romepi-sp3_1.0.0.d; AMD Epyc 7373X Firmware milanpi-sp3_1.0.0.7. Check the vendor advisory for mitigations.

References

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