CVE-2021-26344
HIGHCVSS 8.2/10EPSS 0.16%
Last modified
CVE-2021-26344 is a high-severity vulnerability rated 8.2/10 on the CVSS scale. An out of bounds memory write when processing the AMD PSP1 Configuration Block (APCB) could allow an attacker with access the ability to modify the BIOS image, and the ability to sign the resulting image, to potentially modify the APCB block resulting in arbitrary code execution.. EPSS estimates a 0.16% chance of exploitation in the next 30 days.
Description
An out of bounds memory write when processing the AMD PSP1 Configuration Block (APCB) could allow an attacker with access the ability to modify the BIOS image, and the ability to sign the resulting image, to potentially modify the APCB block resulting in arbitrary code execution.
Metrics
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Amd | Epyc 7203 Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7203p Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 72f3 Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7303 Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7303p Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7313 Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7313p Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7343 Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 73f3 Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7373x Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7413 Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7443 Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7443p Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 74f3 Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7453 Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7473x Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7513 Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7543 Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7543p Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 75f3 Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7573x Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7643 Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7773x Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7643p Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7663 Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7663p Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7713 Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7713p Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7763 Firmware | < milanpi_1.0.0.5 |
| Amd | Epyc 7h12 Firmware | < romepi_1.0.0.c |
| Amd | Epyc 7f72 Firmware | < romepi_1.0.0.c |
| Amd | Epyc 7f52 Firmware | < romepi_1.0.0.c |
| Amd | Epyc 7f32 Firmware | < romepi_1.0.0.c |
| Amd | Epyc 7742 Firmware | < romepi_1.0.0.c |
| Amd | Epyc 7702p Firmware | < romepi_1.0.0.c |
| Amd | Epyc 7702 Firmware | < romepi_1.0.0.c |
| Amd | Epyc 7662 Firmware | < romepi_1.0.0.c |
| Amd | Epyc 7642 Firmware | < romepi_1.0.0.c |
| Amd | Epyc 7552 Firmware | < romepi_1.0.0.c |
| Amd | Epyc 7542 Firmware | < romepi_1.0.0.c |
| Amd | Epyc 7532 Firmware | < romepi_1.0.0.c |
| Amd | Epyc 7502p Firmware | < romepi_1.0.0.c |
| Amd | Epyc 7502 Firmware | < romepi_1.0.0.c |
| Amd | Epyc 7452 Firmware | < romepi_1.0.0.c |
| Amd | Epyc 7402p Firmware | < romepi_1.0.0.c |
| Amd | Epyc 7402 Firmware | < romepi_1.0.0.c |
| Amd | Epyc 7352 Firmware | < romepi_1.0.0.c |
| Amd | Epyc 7302p Firmware | < romepi_1.0.0.c |
| Amd | Epyc 7302 Firmware | < romepi_1.0.0.c |
| Amd | Epyc 7282 Firmware | < romepi_1.0.0.c |
Showing 50 of 69 affected configurations. See NVD for the full list.
References
Timeline
- Published
- Last Modified
- Status
- Modified
Frequently Asked Questions
What is CVE-2021-26344?
An out of bounds memory write when processing the AMD
PSP1 Configuration Block (APCB) could allow an attacker with access the ability
to modify the BIOS image, and the ability to sign the resulting image, to
potentially modify the APCB block resulting in arbitrary code execution.
How severe is CVE-2021-26344?
CVE-2021-26344 has a CVSS score of 8.2/10 (HIGH severity). The EPSS model estimates a 0.16% probability of exploitation in the next 30 days.
How do I fix CVE-2021-26344?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
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Are you affected by CVE-2021-26344?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST