CVE-2021-45970 : What You Need to Know

An issue was discovered in IdeBusDxe in Insyde InsydeH2O with kernel 5.1 before 05.16.25, 5.2 before 05.26.25, 5.3 before 05.35.25, 5.4 before 05.43.25, and 5.5 before 05.51.25. A vulnerability exists in the SMM (System Management Mode) branch that registers a SWSMI handler that does not sufficiently check or validate the allocated buffer pointer (the status code saved at the CommBuffer+4 location).

Understanding CVE-2021-45970

This section will provide insights into the nature and impact of CVE-2021-45970.

What is CVE-2021-45970?

CVE-2021-45970 is a vulnerability found in the SMM branch of IdeBusDxe in Insyde InsydeH2O kernel versions ranging from 5.1 to 5.5. The issue lies in the improper validation of buffer pointers.

The Impact of CVE-2021-45970

The vulnerability in CVE-2021-45970 can potentially lead to security breaches and unauthorized access to system functions due to the lack of proper validation mechanisms.

Technical Details of CVE-2021-45970

This section will delve into the technical aspects of the CVE-2021-45970 vulnerability.

Vulnerability Description

The vulnerability in IdeBusDxe allows for a malicious actor to exploit the SWSMI handler by not adequately validating the allocated buffer pointer, leading to potential security risks.

Affected Systems and Versions

Affected Systems: Insyde InsydeH2O with kernel 5.1 before 05.16.25, 5.2 before 05.26.25, 5.3 before 05.35.25, 5.4 before 05.43.25, and 5.5 before 05.51.25
Affected Versions: n/a

Exploitation Mechanism

The exploitation of this vulnerability involves manipulating the SWSMI handler to bypass the inadequate buffer pointer validation, enabling attackers to execute malicious code in the SMM environment.

Mitigation and Prevention

In this section, you will find recommendations on mitigating the risks associated with CVE-2021-45970.

Immediate Steps to Take

Update to the latest kernel versions provided by Insyde to patch the vulnerability.
Implement proper input validation mechanisms to prevent unauthorized access.

Long-Term Security Practices

Conduct regular security audits and assessments to identify potential vulnerabilities.
Train staff on cybersecurity best practices to enhance overall system security.

Patching and Updates

Regularly monitor and apply security patches and updates released by Insyde to ensure protection against known vulnerabilities.