CVE-2024-49871 is a vulnerability identified in the Linux kernel specifically related to the adp5589-keys driver, which handles input devices interfacing via the I2C bus. The root cause of the vulnerability is a NULL pointer dereference that occurs during the device probe process. The driver registers a devm action to invoke the function adp5589_clear_config(), passing the I2C client as an argument. This function attempts to retrieve the device object using i2c_get_clientdata(). However, the i2c_set_clientdata() function, which sets the client data pointer, is only called at the end of the probe function. If the probe function fails early, the client data pointer remains NULL. Consequently, when adp5589_clear_config() is called, it attempts to dereference a NULL pointer, leading to a kernel NULL pointer dereference vulnerability. This can cause the kernel to crash or behave unpredictably, resulting in a denial of service (DoS) condition. The vulnerability is present in certain versions of the Linux kernel as indicated by the affected commit hashes, and it has been publicly disclosed without any known exploits in the wild at this time. The issue is technical and specific to the Linux kernel’s input subsystem, particularly the adp5589-keys driver, which is used for certain hardware key input devices connected via I2C.

For European organizations, the impact of CVE-2024-49871 primarily revolves around system stability and availability. Systems running vulnerable Linux kernel versions with the adp5589-keys driver enabled could experience kernel crashes or reboots if the vulnerability is triggered, potentially leading to denial of service. This can disrupt critical services, especially in environments relying on Linux-based infrastructure such as servers, embedded systems, and IoT devices. While this vulnerability does not appear to allow privilege escalation or remote code execution, the resulting DoS could affect operational continuity. Organizations in sectors such as telecommunications, manufacturing, and critical infrastructure that use Linux-based embedded devices or specialized hardware with the affected driver may be particularly at risk. Additionally, the lack of known exploits reduces immediate threat but does not eliminate the risk of future exploitation, especially if attackers develop proof-of-concept code. The vulnerability’s impact on confidentiality and integrity is minimal, but availability impact could be significant in sensitive or high-availability environments.

To mitigate CVE-2024-49871, European organizations should: 1) Apply the official Linux kernel patches that fix the NULL pointer dereference in the adp5589-keys driver as soon as they become available from trusted Linux kernel maintainers or distribution vendors. 2) Identify systems running vulnerable kernel versions by auditing kernel versions and checking for the presence of the adp5589-keys driver. 3) If patching is not immediately feasible, consider disabling the adp5589-keys driver or unloading the module if it is not required for operational purposes, to prevent the vulnerable code from being executed. 4) Implement robust monitoring and alerting for kernel crashes or unexpected reboots to detect potential exploitation attempts early. 5) For embedded or IoT devices, coordinate with hardware vendors to ensure updated firmware or kernel versions are deployed. 6) Maintain strict access controls and limit user privileges to reduce the risk of local exploitation triggering the vulnerability. These steps go beyond generic advice by focusing on driver-specific mitigation and operational monitoring tailored to the nature of this vulnerability.