CVE-2026-97987

A flaw was found in the Linux kernel's virtio_input driver. When device registration fails during initialization, the driver removes communication queues without first resetting the device. This allows the virtual device to continue Direct Memory Access (DMA) operations on memory that has already been deallocated, which may result in memory corruption or a Denial of Service (DoS).

A flaw in the Linux kernel virtio_input driver affects the kernel and kernel-rt packages in Red Hat Enterprise Linux 7 and later update streams, Red Hat In-Vehicle OS, and the RHEL CoreOS images used by OpenShift Container Platform. During device probing, the driver marks the virtio device as ready (DRIVER_OK) before calling input_register_device(); if that registration fails, the error path tears down the virtqueues without first resetting the device. The still-live virtio input device can then continue DMA to memory belonging to queues that were already freed, which may result in memory corruption or a denial of service in the guest kernel. Red Hat rates this flaw as MODERATE severity (CVSS 5.5, AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H): exploitation requires local access within a guest that uses virtio input devices and depends on input device registration failing during probe, and the Red Hat assessment considers the confirmed impact to be loss of availability, which is lower than the higher theoretical severity suggested by worst-case analysis of the DMA use-after-free. Red Hat Enterprise Linux 6 is not affected because the vulnerable virtio_input code is not present in that release. Because the flaw is reachable only on a rarely hit error path and requires local access in the guest, the fix is deferred for the affected releases; the residual risk for customers running virtualized guests with virtio input devices is potential guest kernel memory corruption or denial of service.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.