CVE-2022-32475 is a high-severity vulnerability affecting InsydeH2O firmware versions with kernel 5.0 through 5.5. The issue arises from a time-of-check to time-of-use (TOCTOU) race condition in the handling of a shared buffer named VariableRuntimeDxe, which is accessed by both System Management Mode (SMM) and non-SMM code. Specifically, the vulnerability involves Direct Memory Access (DMA) attacks that can exploit this race condition to corrupt System Management RAM (SMRAM). SMRAM is a highly privileged memory region used by SMM to execute firmware-level code with elevated privileges, isolated from the operating system and other software layers. By corrupting SMRAM, an attacker can escalate privileges, potentially gaining control over the system at the firmware level. This can lead to complete compromise of system integrity, confidentiality, and availability. The vulnerability was addressed by kernel-level fixes that also protect chipset and OEM chipset code, mitigating the risk of exploitation. The CVSS 3.1 base score is 7.0, reflecting high severity, with attack vector local (AV:L), requiring high attack complexity (AC:H), low privileges (PR:L), no user interaction (UI:N), unchanged scope (S:U), and high impact on confidentiality, integrity, and availability (C:H/I:H/A:H). No known exploits are currently reported in the wild. The underlying weakness is categorized under CWE-367 (Time-of-check Time-of-use Race Condition). This vulnerability is critical because it targets firmware, which is foundational to system security, and exploitation could bypass traditional OS-level security controls.

For European organizations, the impact of CVE-2022-32475 is significant due to the potential for firmware-level compromise. Successful exploitation could allow attackers to gain persistent, stealthy control over affected devices, bypassing operating system security and antivirus protections. This could lead to data breaches, espionage, sabotage, or ransomware deployment with elevated privileges. Organizations relying on devices with InsydeH2O firmware kernel versions 5.0 to 5.5—commonly found in laptops, desktops, and embedded systems—are at risk. Critical sectors such as finance, healthcare, government, and critical infrastructure in Europe could face severe disruptions and data loss. The ability to corrupt SMRAM also raises concerns about supply chain attacks and firmware backdoors, which are difficult to detect and remediate. Given the local attack vector, the threat is more relevant to insider threats or attackers with physical or local access, but the high impact on confidentiality, integrity, and availability makes it a serious concern for enterprise security.

1. Firmware Updates: Organizations should prioritize applying firmware updates or patches provided by device manufacturers or OEMs that address this vulnerability. Since the patch fixes kernel-level protections and chipset code, timely updates are critical. 2. Hardware Inventory and Assessment: Conduct an inventory to identify devices running InsydeH2O firmware with kernel versions 5.0 through 5.5. 3. Restrict Physical and Local Access: Limit physical and local access to sensitive systems to reduce the risk of local DMA attacks. Employ port control and disable unused DMA-capable interfaces where possible. 4. Enable IOMMU: Use Input-Output Memory Management Unit (IOMMU) features to restrict DMA access to authorized memory regions, mitigating the risk of unauthorized DMA attacks. 5. Monitor Firmware Integrity: Implement firmware integrity monitoring solutions to detect unauthorized modifications to SMRAM or firmware components. 6. Security Awareness: Train IT and security staff to recognize the risks associated with firmware vulnerabilities and the importance of patch management. 7. Collaborate with Vendors: Engage with hardware vendors and OEMs to obtain timely security advisories and patches. 8. Incident Response Preparedness: Prepare for potential firmware compromise scenarios by having robust incident response plans that include firmware re-flashing and hardware replacement if necessary.