#VU75984 Improper Certificate Validation in 1st Gen AMD EPYC Processors and 2nd Gen AMD EPYC Processors - CVE-2021-26406

Vulnerability identifier: #VU75984

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-2021-26406

CWE-ID: CWE-295

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
1st Gen AMD EPYC Processors
Hardware solutions / Firmware
2nd 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 insufficient parsing of Owner's Certificate Authority (OCA) certificates in SEV (AMD Secure Encrypted Virtualization) and SEV-ES user application. A local user can perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

1st Gen AMD EPYC Processors: before NaplesPI 1.0.0.E

2nd Gen AMD EPYC Processors: before RomePI 1.0.0.A

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External links
https://www.amd.com/en/resources/product-security/bulletin/amd-sb-3001.html

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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.