CVE-2021-43615 : What You Need to Know

An issue was discovered in HddPassword in Insyde InsydeH2O with kernel 5.1 before 05.16.23, 5.2 before 05.26.23, 5.3 before 05.35.23, 5.4 before 05.43.22, and 5.5 before 05.51.22. This vulnerability allows an attacker to write fixed or predictable data to SMRAM, potentially leading to escalating privileges to System Management Mode (SMM).

Understanding CVE-2021-43615

What is CVE-2021-43615?

CVE-2021-43615 involves an SMM memory corruption vulnerability in Insyde InsydeH2O, enabling an attacker to write specific data to SMRAM.

The Impact of CVE-2021-43615

The exploitation of this vulnerability could result in an attacker gaining elevated privileges to SMM, posing severe security risks to the system.

Technical Details of CVE-2021-43615

Vulnerability Description

The vulnerability in HddPassword of InsydeH2O allows unauthorized writing of data to SMRAM, potentially leading to privileges escalation.

Affected Systems and Versions

Insyde InsydeH2O with kernel 5.1 before 05.16.23
Insyde InsydeH2O with kernel 5.2 before 05.26.23
Insyde InsydeH2O with kernel 5.3 before 05.35.23
Insyde InsydeH2O with kernel 5.4 before 05.43.22
Insyde InsydeH2O with kernel 5.5 before 05.51.22

Exploitation Mechanism

The vulnerability allows an attacker to manipulate SMRAM, potentially causing privilege escalation to System Management Mode.

Mitigation and Prevention

Immediate Steps to Take

Apply official patches and updates provided by Insyde.
Monitor vendor's security advisories for any related announcements.
Restrict physical access to systems to mitigate direct exploitation opportunities.

Long-Term Security Practices

Regularly update firmware and BIOS to ensure the latest protection measures.
Implement strict access controls and user permissions to limit system accessibility.
Conduct regular security audits and assessments to detect vulnerabilities.

Patching and Updates

Promptly apply the security patches released by Insyde to address and mitigate the CVE-2021-43615 vulnerability.