Technical impact
The vulnerability originates in the Linux kernel's dibs device subsystem, where the lock protecting dibs device state is only initialized during dibs_dev_add(). Because a device can register an interrupt handler before that call, an interrupt may be delivered while the lock remains uninitialized. The interrupt handler, ism_handle_irq(), unconditionally acquires the lock before checking any condition, which can lead to a race and undefined kernel behavior that manifests as a denial of service (kernel crash). This flaw is a direct result of improper initialization.
Affected Systems
Any Linux system running a kernel where the dibs device driver contains the uninitialized lock code is affected. The CVE data does not list specific kernel versions, indicating that any kernel build before the patch that includes this uninitialized lock is at risk. Systems that use the ISM driver or other drivers exposing GID event interrupts are the most directly impacted.
Risk and Exploitability
The reported CVSS score of 9.8 indicates critical severity, but the EPSS score is less than 1%, suggesting a very low probability of exploitation in the wild. Based on the description, it is inferred that the flaw requires local or higher privilege to trigger the relevant interrupt, and that a device capable of generating the GID events is needed. Based on the description, it is inferred that the risk of accidental kernel crash might be high for affected systems. The likelihood of a crafted attacker exploiting this remains low pending the presence of such a device. The issue is not listed in the CISA KEV catalog.
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