CVE-2021-41837 : Vulnerability Insights and Analysis

An issue was discovered in AhciBusDxe in the kernel 5.0 through 5.5 in Insyde InsydeH2O. This vulnerability could lead to escalating privileges to System Management Mode (SMM) through SMM memory corruption.

Understanding CVE-2021-41837

What is CVE-2021-41837?

CVE-2021-41837 is a vulnerability in AhciBusDxe in the Insyde InsydeH2O kernel 5.0 through 5.5. It arises from an Untrusted Pointer Dereference that causes SMM memory corruption, potentially enabling an attacker to write fixed or predictable data to SMRAM.

The Impact of CVE-2021-41837

Exploitation of this vulnerability could result in an attacker gaining escalated privileges to SMM, posing a significant security risk.

Technical Details of CVE-2021-41837

Vulnerability Description

The vulnerability in AhciBusDxe allows attackers to corrupt SMM memory through an Untrusted Pointer Dereference, potentially leading to unauthorized data modification.

Affected Systems and Versions

Affected Systems: Insyde InsydeH2O
Affected Versions: Kernel 5.0 through 5.5

Exploitation Mechanism

By exploiting this vulnerability, an attacker could write specific data to SMRAM, consequently escalating their privileges to SMM.

Mitigation and Prevention

Immediate Steps to Take

Update to the latest kernel version provided by Insyde to patch the vulnerability.
Monitor for any suspicious activities or unauthorized access attempts.

Long-Term Security Practices

Implement strict access controls and least privilege principles.
Regularly update and patch software and firmware to mitigate security risks.

Patching and Updates

Apply security patches promptly to address known vulnerabilities.