CVE-2022-33906 Explained : Impact and Mitigation

A TOCTOU attack on input buffers used for the FwBlockServiceSmm software SMI handler could lead to SMRAM corruption, affecting various kernel versions.

Understanding CVE-2022-33906

This CVE involves DMA transactions targeting input buffers, potentially causing SMRAM corruption through a TOCTOU attack.

What is CVE-2022-33906?

CVE-2022-33906 describes a vulnerability where DMA transactions aimed at input buffers used by the FwBlockServiceSmm software SMI handler could result in SMRAM corruption.

The Impact of CVE-2022-33906

The vulnerability could be exploited to corrupt SMRAM, leading to potential security risks affecting the integrity of the system.

Technical Details of CVE-2022-33906

This section outlines the technical aspects related to the CVE.

Vulnerability Description

The vulnerability arises from DMA transactions directed at input buffers, posing a risk of SMRAM corruption through TOCTOU attacks.

Affected Systems and Versions

Vendor and product details are not available, but the vulnerability impacts kernel versions 5.2, 5.3, 5.4, and 5.5.

Exploitation Mechanism

The issue could be exploited by manipulating DMA transactions to target specific input buffers, triggering SMRAM corruption.

Mitigation and Prevention

Learn how to address and prevent the CVE.

Immediate Steps to Take

Ensure kernel patches are up to date to mitigate the risk of SMRAM corruption through TOCTOU attacks.

Long-Term Security Practices

Implement secure coding practices and regularly update systems to prevent potential vulnerabilities.

Patching and Updates

Refer to kernel versions 5.2: 05.27.23, 5.3: 05.36.23, 5.4: 05.44.23, 5.5: 05.52.23 to patch the vulnerability.