CVE Database›Document archive›CVE-2026-97977

CVE-2026-97977

kernel: Bluetooth: btusb: Fix UAF of btusb_data by rx_work

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Severity

Moderate

Red Hat Product Security

5.5

CVSS 3.1

Review impact separately from score.

Published · September 25, 2026

Updated · October 18, 2026

Description

A flaw was found in the Linux kernel's Bluetooth USB driver. A race condition during device closure or disconnection allows background receive tasks to continue running after the associated device data has been released, leading to a use-after-free (UAF) condition. A local attacker could exploit this flaw to cause a Denial of Service (DoS) by crashing the system or potentially achieve arbitrary code execution.

Statement

A use-after-free flaw was found in the Linux kernel's Bluetooth USB (btusb) driver. When a Bluetooth USB device is closed or disconnected, btusb_close() and btusb_flush() cancel the delayed receive work with the asynchronous cancel_delayed_work(), so a btusb_rx_work() that is already running on another CPU can continue executing after the cancellation and dereference the btusb_data structure that btusb_disconnect() has already freed. A local attacker able to trigger device closure or disconnection could exploit this race condition to crash the system (denial of service) or potentially execute arbitrary code. Red Hat rated this flaw Moderate (CVSS 3.1 score 5.5, AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H), with the primary impact being availability; exploitation requires local access and winning a race window during device teardown.

The kernel and kernel-rt packages in Red Hat Enterprise Linux 8, 9, and 10 are affected, as are RHIVOS 2 and the RHEL 9 based Red Hat CoreOS kernels shipped with OpenShift 4 and 5. RHEL 7 ELS and the RHEL 8.4, 8.6, and 8.8 update streams are not affected because the vulnerable code is not present, and RHEL 6 ELS is out of active support scope. The fix for the affected streams is currently deferred to a future scheduled update; given the Moderate rating, the requirement for local access, and the narrow race window, the residual risk while the fix is pending is considered limited.

CVSS score applicability

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

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.

CVSS / CWE

CVSS 3.1 · 5.5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CWE-825 · Expired Pointer Dereference