CVE-2026-31672

A flaw was found in the Linux kernel's rt2x00usb component, which handles Wi-Fi USB devices. This issue stems from improper management of system memory allocated for USB devices. When a Wi-Fi USB device driver is unloaded without the device being physically disconnected, the system may fail to release the allocated memory, leading to a memory leak. Over time, this could exhaust system resources, potentially causing a Denial of Service (DoS) where the system becomes unresponsive or crashes.

A moderate-severity flaw was found in the Linux kernel's rt2x00usb driver, which handles Wi-Fi USB devices. The USB anchor used by the driver was allocated as a device-managed resource tied to the parent USB device rather than to the USB interface the driver binds to. As a result, when the driver is unbound from the interface without the device being physically disconnected (for example, on probe deferral or configuration changes), the allocated memory is not released, producing a kernel memory leak. A local attacker with the privileges needed to unbind and rebind the driver could repeat this cycle to gradually exhaust kernel memory, ultimately causing a denial of service. Only availability is affected; there is no impact on confidentiality or integrity. Red Hat rated this flaw Moderate severity with CVSS 3.1 score 5.5 (AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H), consistent with the upstream NIST assessment.

The vulnerable code is present in the kernel and kernel-rt packages of Red Hat Enterprise Linux 8, 9, and 10, and in the kernel package of Red Hat In-Vehicle OS 2, which are therefore affected. Red Hat Enterprise Linux 6 and 7 are not affected because the vulnerable code is not present in those releases. For most affected streams the fix is deferred to a future maintenance update; the residual risk of this deferral is considered low because exploitation requires local privileged access to repeatedly unbind the driver, memory accumulates only gradually across such cycles, and no confidentiality or integrity impact exists.

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.