CVE-2022-28806 Explained : Impact and Mitigation

An issue was discovered on certain Fujitsu LIFEBOOK devices with specific BIOS versions before v1.09 (A3510), v2.17 (U9310), v2.30 (U7511/U7411/U7311), v2.33 (U9311), v2.23 (E5510), v2.19 (U7510/U7410), v2.13 (U7310), and v1.09 (E459/E449). The vulnerability allows an attacker to elevate privileges and execute arbitrary code in SMM.

Understanding CVE-2022-28806

This CVE describes a security issue present in certain Fujitsu LIFEBOOK devices that could be exploited by attackers to gain elevated privileges and execute malicious code.

What is CVE-2022-28806?

CVE-2022-28806 is a vulnerability found in the FjGabiFlashCoreAbstractionSmm driver on Fujitsu LIFEBOOK devices with specific BIOS versions. It allows attackers to corrupt memory, change SMI handler code, or modify SMRAM map structures.

The Impact of CVE-2022-28806

Exploitation of this vulnerability could lead an attacker to escalate privileges from ring 0 to ring -2, enabling them to execute arbitrary code in System Management Mode (SMM) on the affected devices.

Technical Details of CVE-2022-28806

This section provides an overview of the vulnerability's technical aspects.

Vulnerability Description

The vulnerability arises from insufficient validation of a Software System Management Interrupt (SWSMI) handler, allowing attackers to write fixed data to SMRAM and potentially corrupt memory.

Affected Systems and Versions

The specific Fujitsu LIFEBOOK devices affected include A3510, U9310, U7511/U7411/U7311, U9311, E5510/E5410, U7510/U7410/U7310, E459/E449 with BIOS versions outlined in the description.

Exploitation Mechanism

Attackers can exploit the vulnerability by manipulating the CommBuffer or other communication buffer contents, leading to corruption in SMRAM memory structure.

Mitigation and Prevention

To address CVE-2022-28806, users and organizations should take immediate and long-term security measures.

Immediate Steps to Take

It is recommended to update the BIOS of affected Fujitsu LIFEBOOK devices to the patched versions provided by the manufacturer to mitigate the vulnerability.

Long-Term Security Practices

Implementing secure coding practices, regular security audits, and user awareness training can help prevent similar exploits in the future.

Patching and Updates

Stay informed about security advisories from Fujitsu and apply security patches promptly to ensure the protection of your devices.