CVE-2021-45969 : Exploit Details and Defense Strategies

An issue was discovered in AhciBusDxe 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 CommBuffer+8 location).

Understanding CVE-2021-45969

This section provides insights into the nature and impact of CVE-2021-45969.

What is CVE-2021-45969?

CVE-2021-45969 is a vulnerability found in AhciBusDxe in Insyde InsydeH2O with specific kernel versions. The issue lies in the inadequate validation of the buffer pointer in the SMM branch.

The Impact of CVE-2021-45969

The vulnerability can lead to potential security breaches and exploitation, compromising system integrity and confidentiality.

Technical Details of CVE-2021-45969

Explore the technical aspects and implications of CVE-2021-45969.

Vulnerability Description

The flaw in the SMM branch allows for the registration of a SWSMI handler without proper validation of the buffer pointer, posing a security risk.

Affected Systems and Versions

Systems: Insyde InsydeH2O with specified kernel versions.
Versions: 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.

Exploitation Mechanism

The vulnerability can be exploited by malicious actors to execute arbitrary code, escalate privileges, or perform other unauthorized actions on affected systems.

Mitigation and Prevention

Learn how to address and prevent CVE-2021-45969 effectively.

Immediate Steps to Take

Apply security patches provided by the vendor promptly.
Implement strict access controls and restrictions on system components.
Monitor system behavior for any suspicious activities indicating exploitation.

Long-Term Security Practices

Conduct regular security audits and assessments to identify and correct vulnerabilities.
Educate users and IT personnel on best security practices and awareness training.

Patching and Updates

Stay updated with security advisories and patches released by Insyde and related vendors to address CVE-2021-45969 effectively.