CVE-2023-27373 : Security Advisory and Response

This CVE record pertains to a security issue identified as CVE-2023-27373, which was reported on February 28, 2023, and subsequently published on August 7, 2023, by MITRE. The vulnerability was found in Insyde InsydeH2O with kernel versions ranging from 5.0 to 5.5. Attackers could exploit this flaw through insufficient input validation, allowing them to manipulate an EFI variable during runtime, resulting in the overlapping of a dynamic BAR setting with SMRAM.

Understanding CVE-2023-27373

This section will delve into the details of CVE-2023-27373, outlining its impact and providing technical insights.

What is CVE-2023-27373?

The CVE-2023-27373 vulnerability exists in Insyde InsydeH2O firmware versions 5.0 to 5.5. It stems from a lack of proper input validation, enabling malicious actors to interfere with an EFI variable during system runtime. This manipulation can lead to the dynamic BAR setting overlapping with SMRAM, creating a security risk.

The Impact of CVE-2023-27373

Exploiting CVE-2023-27373 could result in a critical security breach. By tampering with runtime-accessible EFI variables, attackers can trigger the overlapping of critical memory regions, potentially enabling unauthorized access to sensitive data or the execution of malicious code. This vulnerability poses a severe risk to system integrity and confidentiality.

Technical Details of CVE-2023-27373

This section will outline the technical aspects of CVE-2023-27373, including vulnerability description, affected systems, and exploitation mechanisms.

Vulnerability Description

The vulnerability in Insyde InsydeH2O firmware versions 5.0 through 5.5 arises from inadequate input validation. This oversight allows threat actors to manipulate EFI variables at runtime, leading to the overlap of a dynamic BAR setting with SMRAM, compromising system security.

Affected Systems and Versions

The CVE-2023-27373 vulnerability impacts systems running Insyde InsydeH2O firmware versions 5.0 to 5.5. Organizations utilizing these firmware versions are at risk of exploitation if the necessary security measures are not implemented promptly.

Exploitation Mechanism

Attackers can exploit CVE-2023-27373 by leveraging the lack of input validation in Insyde InsydeH2O firmware. By tampering with a runtime-accessible EFI variable, they can trigger the dynamic BAR setting to overlap with SMRAM, potentially leading to unauthorized access or malicious code execution.

Mitigation and Prevention

To safeguard systems from the risks associated with CVE-2023-27373, proactive mitigation strategies and security measures should be implemented promptly.

Immediate Steps to Take

Organizations should promptly apply security patches provided by Insyde or relevant vendors to address the vulnerability. Additionally, ensuring that access controls and monitoring mechanisms are in place can help detect and prevent potential attacks targeting this vulnerability.

Long-Term Security Practices

Implementing robust security protocols, conducting regular security assessments, and staying informed about firmware updates and security advisories can enhance long-term resilience against similar vulnerabilities in the future.

Patching and Updates

Regularly monitoring for security updates from Insyde and promptly applying patches to address known vulnerabilities is crucial. By maintaining up-to-date firmware versions and security configurations, organizations can reduce the risk of exploitation and enhance overall system security.