CVE-2024-53238 is a vulnerability identified in the Linux kernel's Bluetooth subsystem, specifically within the MediaTek (btmtk) USB driver implementation. The flaw arises from improper initialization of the ISO data anchor during the Bluetooth USB setup flow. The MediaTek driver initializes the ISO data anchor at an incorrect point in the device setup sequence. If an unexpected Bluetooth USB disconnect occurs during this setup, the ISO data anchor remains uninitialized. Subsequently, when the driver attempts to release this anchor during cleanup, it dereferences a NULL pointer, causing a kernel crash (NULL pointer dereference). This results in a denial-of-service (DoS) condition due to the kernel panic or crash. The provided kernel trace confirms the crash occurs in the usb_kill_anchored_urbs function, called during the btusb_mtk_release_iso_intf and btusb_mtk_disconnect routines. This vulnerability affects Linux kernel versions containing the affected MediaTek Bluetooth USB driver code, as identified by the commit hashes referenced. No public exploits are known at this time, and no CVSS score has been assigned. The root cause is a race condition or logic error in the driver’s handling of USB disconnect events during ISO data interface initialization. This flaw is specific to MediaTek Bluetooth USB devices running on Linux systems, which are common in embedded devices, laptops, and some IoT hardware. The vulnerability does not appear to allow privilege escalation or arbitrary code execution but can cause system instability or denial of service by crashing the kernel when the Bluetooth device is disconnected unexpectedly during initialization.

For European organizations, the primary impact of CVE-2024-53238 is potential system instability or denial of service on Linux-based systems using MediaTek Bluetooth USB devices. This includes laptops, desktops, embedded systems, and IoT devices prevalent in enterprise environments. A kernel crash can disrupt critical services, cause data loss, or require system reboots, impacting availability. Organizations relying on Linux for networking, industrial control, or endpoint devices with MediaTek Bluetooth hardware may experience interruptions. While this vulnerability does not directly expose sensitive data or allow remote code execution, the resulting denial of service could be exploited as part of a broader attack chain to degrade system reliability or availability. In sectors such as manufacturing, healthcare, or telecommunications, where Linux-based embedded devices are common, this could lead to operational disruptions. Additionally, the vulnerability could be triggered by local users or automated processes that cause unexpected Bluetooth USB disconnects, potentially as a vector for sabotage or accidental outages. Given the widespread use of Linux in European IT infrastructure and the growing adoption of MediaTek Bluetooth components, the risk of impact is moderate, especially in environments with less rigorous device management or patching practices.

To mitigate CVE-2024-53238, European organizations should: 1) Apply the latest Linux kernel updates that include the patch fixing the MediaTek Bluetooth USB driver initialization sequence. Regularly monitor kernel security advisories and update promptly. 2) Implement device management policies to control and monitor Bluetooth device connections, minimizing unexpected disconnects during device initialization. 3) For critical systems, consider disabling Bluetooth USB devices if not required, or restrict their use to trusted devices only. 4) Employ kernel crash monitoring and automated recovery mechanisms to reduce downtime caused by potential crashes. 5) Conduct thorough testing of Bluetooth device behavior in controlled environments to detect and prevent unexpected disconnect scenarios. 6) Collaborate with hardware vendors to ensure firmware and driver compatibility and security updates are applied. 7) Use endpoint security solutions capable of detecting abnormal device disconnections or kernel crashes related to Bluetooth subsystems. These targeted measures go beyond generic advice by focusing on the specific driver and device behavior that triggers the vulnerability.