CVE-2024-35850 is a vulnerability identified in the Linux kernel's Bluetooth subsystem, specifically related to Qualcomm ROME Bluetooth controllers. The issue arises when these controllers are registered via the Bluetooth line discipline, where the Host Controller Interface (HCI) UART serdev pointer can be NULL. The vulnerability is a NULL-pointer dereference caused by the absence of a sanity check in the setup() function for non-serdev controllers. When the setup() function is called without verifying that the serdev pointer is non-NULL, it leads to a NULL-pointer dereference, which typically results in a kernel crash (kernel panic) or system instability. This flaw is a classic example of improper input validation and error handling in kernel code. The vulnerability affects certain Linux kernel versions identified by the commit hash e9b3e5b8c65733f626a7ee919c4bc895b51d7bb2. Although no known exploits are currently reported in the wild, the flaw could be triggered by an attacker with the ability to interact with the Bluetooth subsystem, potentially causing denial of service (DoS) through system crashes. Since the issue is in the kernel Bluetooth driver for Qualcomm ROME controllers, it specifically impacts systems using these controllers and running vulnerable Linux kernel versions. The fix involves adding a missing sanity check to prevent the NULL-pointer dereference, thereby improving the robustness of the Bluetooth driver code.

For European organizations, the primary impact of CVE-2024-35850 is the potential for denial of service attacks on Linux systems utilizing Qualcomm ROME Bluetooth controllers. This could lead to unexpected system crashes or reboots, disrupting business operations, especially in environments where Bluetooth connectivity is critical (e.g., IoT deployments, industrial control systems, or enterprise laptops and mobile devices). Confidentiality and integrity impacts are minimal since the vulnerability does not directly allow code execution or privilege escalation. However, availability is affected due to the risk of kernel panics. Organizations relying on Linux-based infrastructure with Bluetooth capabilities may experience operational downtime, which could affect productivity and service availability. The lack of known exploits reduces immediate risk, but the vulnerability should be addressed promptly to prevent potential future exploitation. Additionally, embedded systems and devices in sectors such as manufacturing, healthcare, and transportation that use Linux with Qualcomm Bluetooth hardware could be vulnerable to targeted disruption.

To mitigate CVE-2024-35850, organizations should: 1) Identify Linux systems running vulnerable kernel versions, particularly those using Qualcomm ROME Bluetooth controllers. 2) Apply the official Linux kernel patches that add the missing sanity check to the Bluetooth driver code as soon as they become available. 3) If patching is not immediately possible, consider disabling Bluetooth functionality on affected systems to prevent triggering the vulnerability. 4) Monitor system logs for unusual Bluetooth-related errors or kernel panics that could indicate attempts to exploit this flaw. 5) Implement network segmentation and access controls to limit exposure of vulnerable systems to untrusted Bluetooth devices or networks. 6) Maintain up-to-date asset inventories to quickly identify affected devices and prioritize patching efforts. 7) Engage with hardware vendors to confirm the presence of Qualcomm ROME controllers and obtain vendor-specific guidance or firmware updates if applicable.