CVE-2021-43522 : Vulnerability Insights and Analysis

An issue was discovered in Insyde InsydeH2O with kernel 5.1 through 2021-11-08, 5.2 through 2021-11-08, and 5.3 through 2021-11-08. This vulnerability could allow an attacker to escalate privileges to System Management Mode (SMM) by corrupting SMM memory.

Understanding CVE-2021-43522

What is CVE-2021-43522?

CVE-2021-43522 is a vulnerability in Insyde InsydeH2O firmware that allows an attacker to write fixed or predictable data to SMRAM, potentially leading to privilege escalation to SMM.

The Impact of CVE-2021-43522

This vulnerability could be exploited to escalate privileges to System Management Mode (SMM), a highly privileged operating mode in x86 processors.

Technical Details of CVE-2021-43522

Vulnerability Description

The StorageSecurityCommandDxe SMM memory corruption vulnerability in Insyde InsydeH2O firmware allows attackers to write fixed or predictable data to SMRAM.

Affected Systems and Versions

Insyde InsydeH2O firmware versions 5.1 through 2021-11-08
Insyde InsydeH2O firmware versions 5.2 through 2021-11-08
Insyde InsydeH2O firmware versions 5.3 through 2021-11-08

Exploitation Mechanism

The vulnerability enables attackers to corrupt SMM memory, granting them the ability to write specific data to SMRAM, potentially leading to privilege escalation to SMM.

Mitigation and Prevention

Immediate Steps to Take

Monitor vendor security advisories for patches and updates related to CVE-2021-43522.
Implement strong firmware and system security practices to mitigate potential exploits.
Restrict physical access to systems running vulnerable firmware.

Long-Term Security Practices

Regularly update firmware to the latest versions to address known vulnerabilities.
Employ least privilege principles to restrict access to critical system components.

Patching and Updates

Apply security patches and firmware updates provided by Insyde or respective vendors to remediate CVE-2021-43522.