#VU63689 Buffer overflow in 2nd Gen AMD EPYC Processors and 3rd Gen AMD EPYC Processors - CVE-2021-26364

Vulnerability identifier: #VU63689

Vulnerability risk: Low

CVSSv4.0: 4.3 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-26364

CWE-ID: CWE-119

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
2nd Gen AMD EPYC Processors
Hardware solutions / Firmware
3rd Gen AMD EPYC Processors
Hardware solutions / Firmware

Vendor: AMD

Description

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to a boundary error in an SMU mailbox register. A local user can force SMU to read outside of the SRAM address range and perform a denial of service attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

2nd Gen AMD EPYC Processors: before RomePI-SP3_1.0.0.D

3rd Gen AMD EPYC Processors: before MilanPI-SP3_1.0.0.7

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External links
https://www.amd.com/en/corporate/product-security/bulletin/amd-sb-1028

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.