CVE-2021-26350 : What You Need to Know

A TOCTOU race condition in SMU may allow for the caller to obtain and manipulate the address of a message port register which may result in a potential denial of service.

Understanding CVE-2021-26350

This CVE-2021-26350 affects EPYC™ Processors by AMD and was made public on May 10, 2022.

What is CVE-2021-26350?

CVE-2021-26350 is a Time-of-Check Time-of-Use (TOCTOU) race condition in SMU (System Management Unit) in EPYC™ Processors. An attacker could exploit this vulnerability to manipulate the address of a message port register, leading to a potential denial of service.

The Impact of CVE-2021-26350

The impact of CVE-2021-26350 is the potential denial of service caused by the manipulation of the address of a message port register through the TOCTOU race condition in SMU.

Technical Details of CVE-2021-26350

This section provides more technical insights into the vulnerability.

Vulnerability Description

The vulnerability arises from a TOCTOU race condition in SMU, allowing an attacker to manipulate the message port register's address.

Affected Systems and Versions

EPYC™ Processors by AMD are affected by this CVE. The specific affected versions are listed as 'various.'

Exploitation Mechanism

Attackers may exploit this vulnerability by leveraging the race condition to obtain and manipulate the message port register's address.

Mitigation and Prevention

To protect systems from CVE-2021-26350, certain steps must be taken to ensure security.

Immediate Steps to Take

Immediately review the provided advisory by AMD and apply any relevant patches or fixes to mitigate the risk of exploitation.

Long-Term Security Practices

Implement robust security measures, follow best practices, and maintain regular security updates to defend against potential vulnerabilities.

Patching and Updates

Regularly check for updates from AMD and apply patches promptly to address any known vulnerabilities in EPYC™ Processors.