CVE-2022-35408 : Security Advisory and Response

Insyde InsydeH2O with kernel 5.0 through 5.5 is impacted by a critical vulnerability that can lead to arbitrary code execution in System Management Mode (SMM) and privilege escalation. This vulnerability exists in the SMM driver in UsbLegacyControlSmm, allowing an attacker to manipulate function pointers, potentially resulting in a severe security breach.

Understanding CVE-2022-35408

This section will delve into the specifics of the CVE-2022-35408 vulnerability, its impact, technical details, and mitigation strategies.

What is CVE-2022-35408?

CVE-2022-35408 is a security flaw present in Insyde InsydeH2O firmware versions 5.0 through 5.5. The vulnerability arises due to an SMM callout vulnerability in the SMM driver in UsbLegacyControlSmm, providing attackers with the opportunity to execute arbitrary code in SMM.

The Impact of CVE-2022-35408

The security vulnerability in CVE-2022-35408 poses a significant threat as attackers can exploit it to execute malicious code in System Management Mode (SMM). This could potentially lead to privilege escalation and compromise the integrity and confidentiality of the system.

Technical Details of CVE-2022-35408

To address the CVE-2022-35408 vulnerability effectively, it is crucial to understand the technical aspects related to the issue, including the vulnerability description, affected systems and versions, and the exploitation mechanism.

Vulnerability Description

The vulnerability in Insyde InsydeH2O with kernel 5.0 through 5.5 allows attackers to manipulate function pointers in the EFI_BOOT_SERVICES table, leading to arbitrary code execution in SMM. This manipulation occurs before the USB System Management Interrupt (SMI) handler initiates, creating a window of opportunity for exploitation.

Affected Systems and Versions

Insyde InsydeH2O firmware versions 5.0 through 5.5 are confirmed to be affected by CVE-2022-35408, making systems running these versions vulnerable to potential exploitation.

Exploitation Mechanism

Attackers can exploit the CVE-2022-35408 vulnerability by leveraging the SMM callout vulnerability in the UsbLegacyControlSmm driver to overwrite function pointers, ultimately executing arbitrary code in System Management Mode (SMM) and possibly elevating their privileges.

Mitigation and Prevention

Addressing CVE-2022-35408 requires a comprehensive approach to mitigate the risks associated with the vulnerability. Implementing immediate steps, adopting long-term security practices, and applying relevant patches and updates are essential for safeguarding systems.

Immediate Steps to Take

Immediate actions to mitigate the CVE-2022-35408 vulnerability include restricting access to sensitive system functions, monitoring for unusual SMI handler activity, and maintaining heightened security awareness to detect potential exploitation attempts.

Long-Term Security Practices

Establishing robust security protocols, conducting regular security assessments, and ensuring timely software updates and patches are fundamental long-term practices to enhance the overall security posture and resilience against similar vulnerabilities.

Patching and Updates

Vendor-supplied patches and updates should be promptly applied to systems running affected versions of Insyde InsydeH2O firmware to remediate the CVE-2022-35408 vulnerability and fortify system defenses against potential attacks.