CVE-2024-26997 is a vulnerability identified in the Linux kernel specifically affecting the USB driver subsystem, more precisely the DesignWare Core USB 2.0 (dwc2) host controller driver. The issue stems from a dereference bug in the Direct DMA (DDMA) completion flow within the dwc2 host driver. This flaw involves improper handling of a variable during the DDMA completion process, which can lead to a dereference of an invalid or null pointer. Such dereference issues typically cause kernel crashes (denial of service) or may potentially be exploited to execute arbitrary code with kernel privileges if an attacker can carefully craft USB device interactions or data flows. The vulnerability affects multiple Linux kernel versions identified by specific commit hashes, indicating it is present in recent kernel builds prior to the fix. The fix involves correcting the variable dereference logic to ensure safe handling during the DDMA completion phase. No known exploits are currently reported in the wild, and no CVSS score has been assigned yet. The vulnerability was reserved in February 2024 and published in May 2024. The affected component, dwc2, is widely used in embedded systems, IoT devices, and some general-purpose Linux systems that rely on this USB host controller driver. Because the issue is in the kernel USB stack, exploitation would require local or physical access to the USB interface or the ability to emulate a malicious USB device. This vulnerability could be leveraged to cause system instability or potentially escalate privileges if exploited successfully.

For European organizations, the impact of CVE-2024-26997 depends largely on the deployment of Linux systems using the dwc2 USB host controller driver. Many embedded devices, industrial control systems, and IoT devices running Linux in sectors such as manufacturing, telecommunications, and critical infrastructure may be affected. A successful exploit could lead to denial of service via kernel crashes, disrupting operations and causing downtime. In more severe cases, attackers with physical or local access could escalate privileges, compromising system integrity and confidentiality. This is particularly concerning for organizations with stringent security requirements such as financial institutions, healthcare providers, and government agencies in Europe. The lack of known exploits currently limits immediate risk, but the presence of this vulnerability in the Linux kernel—a core component of many systems—means that attackers could develop exploits in the future. European organizations with large Linux deployments should prioritize patching to mitigate potential risks. The vulnerability also poses a risk to supply chain security, as embedded Linux devices are common in European manufacturing and telecommunications infrastructure.

1. Immediate application of the official Linux kernel patches that address the DDMA completion flow dereference issue is critical. Organizations should track kernel updates from trusted sources and deploy them promptly. 2. For embedded and IoT devices running affected Linux versions, coordinate with device vendors to obtain firmware updates that include the patched kernel. 3. Implement strict physical security controls to limit unauthorized physical access to USB ports, reducing the risk of malicious USB device insertion. 4. Employ USB device whitelisting or disable unused USB ports where feasible to minimize attack surface. 5. Monitor system logs and kernel messages for unusual USB-related errors or crashes that could indicate exploitation attempts. 6. Conduct regular vulnerability assessments and penetration testing focusing on USB interfaces and kernel-level security. 7. For critical infrastructure, consider network segmentation and isolation of vulnerable devices to contain potential compromise. 8. Maintain an inventory of Linux systems and their kernel versions to identify and prioritize patching of affected hosts.