CVE-2020-27339 : Exploit Details and Defense Strategies

Insyde InsydeH2O 5.x kernel vulnerability allows corruption of firmware or OS memory.

Understanding CVE-2020-27339

This CVE involves a vulnerability in certain SMM drivers in the Insyde InsydeH2O 5.x kernel.

What is CVE-2020-27339?

The vulnerability arises from the incorrect validation of CommBuffer and CommBufferSize parameters, enabling attackers to corrupt firmware or OS memory.

The Impact of CVE-2020-27339

The vulnerability can lead to potential corruption of firmware or OS memory, posing a risk to system integrity and data security.

Technical Details of CVE-2020-27339

This section delves into the technical aspects of the CVE.

Vulnerability Description

The vulnerability in Insyde InsydeH2O 5.x kernel allows callers to corrupt firmware or OS memory due to inadequate validation of certain parameters.

Affected Systems and Versions

Affected systems: Insyde InsydeH2O 5.x kernel
Fixed versions for affected drivers: AhciBusDxe, IdeBusDxe, NvmExpressDxe, SdHostDriverDxe, and SdMmcDeviceDxe drivers (versions 05.16.25, 05.26.25, 05.35.25, 05.43.25, and 05.51.25 for Kernel 5.1 through 5.5)

Exploitation Mechanism

The vulnerability allows attackers to manipulate CommBuffer and CommBufferSize parameters to corrupt firmware or OS memory.

Mitigation and Prevention

Protecting systems from CVE-2020-27339 is crucial for maintaining security.

Immediate Steps to Take

Apply patches provided by the vendor for the affected drivers and kernel versions.
Monitor for any unusual system behavior that could indicate exploitation.

Long-Term Security Practices

Regularly update system firmware and software to prevent vulnerabilities.
Implement security best practices to enhance overall system security.

Patching and Updates

Ensure timely installation of security patches and updates to mitigate the risk of exploitation.