CVE-2021-26331

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-11-16 · updated 2026-06-17
Weakness: CWE-20

Description

AMD System Management Unit (SMU) contains a potential issue where a malicious user may be able to manipulate mailbox entries leading to arbitrary code execution.

Affected products

AMD Epyc 7001 Firmware: before naplespi-sp3_1.0.0.g — fixed in naplespi-sp3_1.0.0.g
AMD Epyc 7002 Firmware: before romepi-sp3_1.0.0.c — fixed in romepi-sp3_1.0.0.c
AMD Epyc 7003 Firmware: before milanpi-sp3_1.0.0.4 — fixed in milanpi-sp3_1.0.0.4
AMD Epyc 7232P Firmware: before romepi-sp3_1.0.0.c — fixed in romepi-sp3_1.0.0.c
AMD Epyc 7251 Firmware: before naplespi-sp3_1.0.0.g — fixed in naplespi-sp3_1.0.0.g
AMD Epyc 7252 Firmware: before romepi-sp3_1.0.0.c — fixed in romepi-sp3_1.0.0.c
AMD Epyc 7262 Firmware: before romepi-sp3_1.0.0.c — fixed in romepi-sp3_1.0.0.c
AMD Epyc 7272 Firmware: before romepi-sp3_1.0.0.c — fixed in romepi-sp3_1.0.0.c
AMD Epyc 7281 Firmware: before naplespi-sp3_1.0.0.g — fixed in naplespi-sp3_1.0.0.g
AMD Epyc 7282 Firmware: before romepi-sp3_1.0.0.c — fixed in romepi-sp3_1.0.0.c
AMD Epyc 72F3 Firmware: before milanpi-sp3_1.0.0.4 — fixed in milanpi-sp3_1.0.0.4
AMD Epyc 7301 Firmware: before naplespi-sp3_1.0.0.g — fixed in naplespi-sp3_1.0.0.g
AMD Epyc 7302 Firmware: before romepi-sp3_1.0.0.c — fixed in romepi-sp3_1.0.0.c
AMD Epyc 7302P Firmware: before romepi-sp3_1.0.0.c — fixed in romepi-sp3_1.0.0.c
AMD Epyc 7313 Firmware: before milanpi-sp3_1.0.0.4 — fixed in milanpi-sp3_1.0.0.4
AMD Epyc 7313P Firmware: before milanpi-sp3_1.0.0.4 — fixed in milanpi-sp3_1.0.0.4
AMD Epyc 7343 Firmware: before milanpi-sp3_1.0.0.4 — fixed in milanpi-sp3_1.0.0.4
AMD Epyc 7351 Firmware: before naplespi-sp3_1.0.0.g — fixed in naplespi-sp3_1.0.0.g
AMD Epyc 7351P Firmware: before naplespi-sp3_1.0.0.g — fixed in naplespi-sp3_1.0.0.g
AMD Epyc 7352 Firmware: before romepi-sp3_1.0.0.c — fixed in romepi-sp3_1.0.0.c
AMD Epyc 73F3 Firmware: before milanpi-sp3_1.0.0.4 — fixed in milanpi-sp3_1.0.0.4
AMD Epyc 7401 Firmware: before naplespi-sp3_1.0.0.g — fixed in naplespi-sp3_1.0.0.g
AMD Epyc 7401P Firmware: before naplespi-sp3_1.0.0.g — fixed in naplespi-sp3_1.0.0.g
AMD Epyc 7402 Firmware: before romepi-sp3_1.0.0.c — fixed in romepi-sp3_1.0.0.c
AMD Epyc 7402P Firmware: before romepi-sp3_1.0.0.c — fixed in romepi-sp3_1.0.0.c
AMD Epyc 7413 Firmware: before milanpi-sp3_1.0.0.4 — fixed in milanpi-sp3_1.0.0.4
AMD Epyc 7443 Firmware: before milanpi-sp3_1.0.0.4 — fixed in milanpi-sp3_1.0.0.4
AMD Epyc 7443P Firmware: before milanpi-sp3_1.0.0.4 — fixed in milanpi-sp3_1.0.0.4
AMD Epyc 7451 Firmware: before naplespi-sp3_1.0.0.g — fixed in naplespi-sp3_1.0.0.g
AMD Epyc 7452 Firmware: before romepi-sp3_1.0.0.c — fixed in romepi-sp3_1.0.0.c

How to fix

Upgrade to a fixed version: AMD Epyc 7001 Firmware naplespi-sp3_1.0.0.g; AMD Epyc 7002 Firmware romepi-sp3_1.0.0.c; AMD Epyc 7003 Firmware milanpi-sp3_1.0.0.4; AMD Epyc 7232P Firmware romepi-sp3_1.0.0.c; AMD Epyc 7251 Firmware naplespi-sp3_1.0.0.g; AMD Epyc 7252 Firmware romepi-sp3_1.0.0.c; AMD Epyc 7262 Firmware romepi-sp3_1.0.0.c; AMD Epyc 7272 Firmware romepi-sp3_1.0.0.c; AMD Epyc 7281 Firmware naplespi-sp3_1.0.0.g; AMD Epyc 7282 Firmware romepi-sp3_1.0.0.c; AMD Epyc 72F3 Firmware milanpi-sp3_1.0.0.4; AMD Epyc 7301 Firmware naplespi-sp3_1.0.0.g. Check the vendor advisory for mitigations.

References

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