#VU63692 Cryptographic issues in AMD products - CVE-2021-46744

Vulnerability identifier: #VU63692

Vulnerability risk: Low

CVSSv4.0: 1.1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-46744

CWE-ID: CWE-310

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
1st Gen AMD EPYC Processors
Hardware solutions / Firmware
2nd Gen AMD EPYC Processors
Hardware solutions / Firmware
3rd Gen AMD EPYC Processors
Hardware solutions / Firmware
AMD EPYC Embedded Processors
Hardware solutions / Firmware

Vendor: AMD

Description

The vulnerability allows a local user to gain access to sensitive information.

The vulnerability exists due to a ciphertext side channel attack where data in specific cryptographic algorithms can be inferred in a SEV guest by monitoring the ciphertext values over time. A local user with access to the hypervisor can gain access to sensitive information, related to the guest OS.

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

1st Gen AMD EPYC Processors: All versions

2nd Gen AMD EPYC Processors: All versions

3rd Gen AMD EPYC Processors: All versions

AMD EPYC Embedded Processors: All versions

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External links
https://www.amd.com/en/corporate/product-security/bulletin/amd-sb-1033
https://www.amd.com/system/files/documents/221404394-a_security_wp_final.pdf

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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.