CVE-2025-22128 is a vulnerability identified in the Linux kernel specifically affecting the ath12k wireless driver, which manages certain Qualcomm Atheros Wi-Fi chipsets. The issue arises in the handling of IRQ (Interrupt Request) affinity hints during error paths when freeing IRQs. In systems where the driver uses a shared IRQ due to platform limitations, the IRQ affinity hint is set immediately after IRQ vector allocation in the function ath12k_pci_msi_alloc(). However, if a subsequent function requesting the IRQ fails and attempts to free the IRQ, the affinity hint is not cleared before calling ath12k_pci_free_irq(). This leads to a warning from the Linux kernel's IRQ core subsystem, which expects the affinity hint to be cleared before freeing the IRQ. The warning is triggered by a kernel check that flags the presence of a non-null affinity hint during IRQ freeing, indicating improper cleanup. The fix involves explicitly clearing the IRQ affinity hint before invoking ath12k_pci_free_irq() in the error path, ensuring proper resource cleanup and preventing kernel warnings. Although the affinity hint is cleared again later in the error path, the early clearing is necessary to avoid the warning and potential instability. This vulnerability does not appear to cause direct memory corruption or privilege escalation but may lead to kernel warnings and potential instability in the IRQ handling subsystem of affected Linux systems using the ath12k driver. No known exploits are reported in the wild, and no CVSS score has been assigned yet.

For European organizations, the impact of CVE-2025-22128 is primarily related to system stability and reliability rather than direct security breaches. Organizations relying on Linux systems with Qualcomm Atheros ath12k Wi-Fi chipsets—common in many laptops, embedded devices, and network equipment—may experience kernel warnings or instability during error conditions involving IRQ handling. This could lead to unexpected system behavior, degraded network performance, or in rare cases, system crashes if the IRQ subsystem is compromised. While the vulnerability does not directly expose systems to remote code execution or privilege escalation, the resulting instability could disrupt critical services, especially in environments where wireless connectivity is essential. For sectors such as telecommunications, manufacturing, and critical infrastructure in Europe, where Linux-based embedded systems are prevalent, this could translate into operational disruptions. However, the absence of known exploits and the nature of the issue suggest a low immediate risk of targeted attacks. Nonetheless, maintaining kernel stability is crucial for compliance with operational security standards and ensuring uninterrupted service delivery.

To mitigate CVE-2025-22128, European organizations should: 1) Apply the latest Linux kernel updates that include the patch fixing the IRQ affinity hint clearing in the ath12k driver error path. This is the definitive fix and prevents the kernel warnings and potential instability. 2) Identify and inventory systems using the ath12k driver, focusing on devices with Qualcomm Atheros Wi-Fi chipsets, to prioritize patching efforts. 3) For embedded or specialized devices where kernel updates are not immediately feasible, consider disabling or limiting the use of affected wireless interfaces temporarily to reduce exposure to IRQ handling errors. 4) Monitor kernel logs for IRQ core warnings related to affinity hints, which can indicate the presence of this issue and help in early detection. 5) Engage with hardware vendors and Linux distribution maintainers to ensure timely delivery of patches and updates. 6) Implement robust system monitoring and alerting to detect any instability or crashes potentially linked to IRQ handling issues. These steps go beyond generic advice by focusing on targeted patching, device inventory, and proactive monitoring specific to this vulnerability.