CVE-2021-26321 Explained : Impact and Mitigation
Discover the impact of CVE-2021-26321 on AMD EPYC processors. Learn about the vulnerability, affected systems, and mitigation steps to secure your systems.
A vulnerability has been identified in AMD EPYC processors, specifically affecting 1st Gen AMD EPYC, 2nd Gen AMD EPYC, and 3rd Gen AMD EPYC.
Understanding CVE-2021-26321
This CVE involves insufficient ID command validation in the SEV Firmware, which could lead to a denial-of-service attack by a local authenticated attacker targeting the PSP.
What is CVE-2021-26321?
The vulnerability in AMD EPYC processors allows a local authenticated attacker to disrupt the PSP's functionality by exploiting inadequate ID command validation in the SEV Firmware.
The Impact of CVE-2021-26321
The impact of this vulnerability is the potential for a denial-of-service attack, compromising the availability and security of affected systems utilizing the vulnerable AMD EPYC processors.
Technical Details of CVE-2021-26321
The technical details of CVE-2021-26321 include:
Vulnerability Description
The vulnerability arises from inadequate validation of ID commands in the SEV Firmware, creating an avenue for local authenticated attackers to disrupt PSP operation.
Affected Systems and Versions
- 1st Gen AMD EPYC: Versions prior to NaplesPI-SP3_1.0.0.G
- 2nd Gen AMD EPYC: Versions prior to RomePI-SP3_1.0.0.C
- 3rd Gen AMD EPYC: Versions prior to MilanPI-SP3_1.0.0.4
Exploitation Mechanism
The vulnerability can be exploited by a local authenticated attacker to trigger a denial-of-service condition on the PSP through the SEV Firmware.
Mitigation and Prevention
To address CVE-2021-26321, follow these steps:
Immediate Steps to Take
- Apply patches or updates provided by AMD to mitigate the vulnerability.
- Monitor AMD's security advisories for any further recommendations or developments.
Long-Term Security Practices
- Implement least privilege access controls to limit potential attack vectors.
- Regularly update firmware and security patches to safeguard against known vulnerabilities.
Patching and Updates
Ensure timely installation of AMD-provided patches and firmware updates to protect against exploits targeting CVE-2021-26321.