CVE-2024-50192 is a vulnerability identified in the Linux kernel specifically related to the Generic Interrupt Controller version 4 (GICv4) implementation, which is used in ARM architecture systems to manage interrupts. The issue arises in the irqchip/gic-v4 code where there is a race condition involving Virtual Processing Elements (VPEs). A VPE represents a virtual CPU in a virtualized environment. The vulnerability allows userspace processes a small window of opportunity to force a change of affinity for a VPE that has already been unmapped (i.e., marked as no longer active or assigned), but where the corresponding doorbell interrupt is still visible in the /proc/irq/ interface. This race condition could lead to inconsistent or unexpected behavior in interrupt handling, potentially causing system instability or incorrect interrupt routing. The fix involves synchronizing the vmapp_count variable, which tracks whether a VPE is mapped, across both GICv4.0 and GICv4.1 implementations and returning an error if an operation is attempted on an unmapped VPE. This patch effectively closes the race window by ensuring that operations on dying VPEs are rejected, preventing the race condition from being exploited. The vulnerability does not have any known exploits in the wild as of the publication date, and no CVSS score has been assigned yet. The affected versions are specific Linux kernel commits identified by their hashes, indicating that this is a recent and low-level kernel issue primarily impacting ARM-based virtualized environments using GICv4 interrupt controllers.

For European organizations, the impact of CVE-2024-50192 depends largely on their use of ARM-based virtualized infrastructure running Linux kernels with GICv4 interrupt controllers. Organizations operating cloud services, telecommunications infrastructure, or embedded systems using ARM virtualization could face risks of system instability or denial of service due to improper interrupt handling if this vulnerability is exploited. While there is no evidence of active exploitation, the race condition could be leveraged by a malicious insider or attacker with local user privileges to disrupt virtual machine operations or cause unpredictable behavior in critical systems. This could impact confidentiality and integrity indirectly if system crashes or misrouting of interrupts lead to data corruption or service outages. Given the kernel-level nature of the vulnerability, successful exploitation could affect the availability of virtualized services, which is critical for sectors such as finance, healthcare, and industrial control systems prevalent in Europe. However, the requirement for local user access and the specificity to ARM GICv4 virtualization limits the scope to specialized environments rather than general-purpose Linux deployments.

European organizations should prioritize updating their Linux kernels to versions that include the patch for CVE-2024-50192 as soon as it becomes available. Specifically, kernel maintainers and system administrators should monitor official Linux kernel repositories and security advisories for the patched commits that synchronize vmapp_count handling in GICv4 implementations. For environments using ARM-based virtualization, it is critical to audit and restrict local user privileges to prevent unauthorized users from attempting to manipulate VPE affinity. Additionally, organizations should implement rigorous monitoring of /proc/irq/ and related kernel interfaces for anomalous activity that could indicate attempts to exploit this race condition. Virtualization platforms should be configured to isolate critical workloads and minimize the attack surface exposed to userspace processes. Finally, testing updated kernels in staging environments before deployment can help ensure stability and compatibility with existing virtualized workloads.