CVE-2024-27043 is a use-after-free vulnerability identified in the Linux kernel's Digital Video Broadcasting (DVB) subsystem, specifically within the media/dvbdev component. The issue arises in the dvb_register_device function, where a pointer (*pdvbdev) is assigned to a dvbdev structure that may be freed during error-handling paths without resetting the pointer to NULL. This leads to a dangling pointer scenario. Subsequent calls, such as dvb_unregister_device and its downstream functions (dvb_remove_device, dvb_device_put, kref_put), may operate on this freed memory, causing use-after-free conditions. Use-after-free vulnerabilities can lead to undefined behavior including kernel crashes (denial of service), memory corruption, or potentially privilege escalation if exploited. The vulnerability affects multiple versions of the Linux kernel identified by the commit hash b61901024776b25ce7b8edc31bb1757c7382a88e. Although no known exploits are reported in the wild, the flaw resides in a critical kernel subsystem managing DVB devices, which are used for digital TV and multimedia streaming hardware. The absence of a CVSS score indicates this is a newly disclosed issue, but the technical details confirm the vulnerability is real and requires attention. The root cause is improper pointer management in error handling, a common source of kernel vulnerabilities. The fix involves ensuring that after dvbdev is freed, the pointer *pdvbdev is set to NULL to prevent use-after-free dereferencing.

For European organizations, the impact of CVE-2024-27043 depends largely on the deployment of Linux systems utilizing DVB hardware or drivers. Many European countries have widespread use of digital TV and multimedia streaming infrastructure, often running on Linux-based embedded systems or servers. Exploitation of this vulnerability could allow a local attacker or a malicious process with access to DVB device interfaces to trigger a kernel crash, causing denial of service. More critically, if exploited with crafted inputs, it could lead to arbitrary code execution in kernel space, resulting in privilege escalation and full system compromise. This poses risks to critical infrastructure, media companies, telecommunications providers, and enterprises relying on Linux servers for streaming or broadcasting services. The vulnerability could also affect embedded devices used in smart city deployments or IoT systems in Europe that incorporate DVB components. Although no public exploits exist yet, the potential for exploitation in high-value environments means European organizations should prioritize patching. The impact on confidentiality, integrity, and availability is significant if exploited, especially given the kernel-level nature of the flaw.

European organizations should take the following specific mitigation steps: 1) Identify all Linux systems running kernels with the affected commit hashes or versions, focusing on those with DVB hardware or software components installed. 2) Apply the official Linux kernel patches that fix the use-after-free by setting *pdvbdev to NULL after deallocation. If vendor-specific distributions are used (e.g., Ubuntu, Debian, Red Hat), monitor their security advisories for backported fixes and apply them promptly. 3) For embedded or specialized devices where kernel patching is not immediately feasible, consider disabling DVB device support if not required, to reduce attack surface. 4) Implement strict access controls to limit which users or processes can interact with DVB devices, minimizing the risk of local exploitation. 5) Monitor system logs and kernel messages for unusual crashes or errors related to DVB device registration/unregistration, which may indicate attempted exploitation. 6) Engage with hardware and software vendors to ensure timely updates and support for affected devices. 7) Incorporate this vulnerability into vulnerability management and patching cycles, prioritizing systems exposed to untrusted users or networks. These targeted actions go beyond generic advice by focusing on the DVB subsystem and kernel patching strategies specific to this flaw.