Bluetooth: hci_sync Memory Leak in Linux Kernel

Publication date: 2026-05-01

Last updated on: 2026-05-08

Assigner: kernel.org

Description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_sync: fix leaks when hci_cmd_sync_queue_once fails When hci_cmd_sync_queue_once() returns with error, the destroy callback will not be called. Fix leaking references / memory on these failures.

CVSS Scores

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Meta Information

Published

2026-05-01

Last Modified

2026-05-08

Generated

2026-07-06

AI Q&A

2026-05-01

EPSS Evaluated

2026-07-05

NVD

CVE-2026-43021

EUVD

EUVD-2026-26620

Affected Vendors & Products

Vendor	Product	Version / Range
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	From 6.19 (inc) to 6.19.12 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-401	The product does not sufficiently track and release allocated memory after it has been used, making the memory unavailable for reallocation and reuse.

Attack-Flow Graph

Executive Summary

This vulnerability exists in the Linux kernel's Bluetooth subsystem, specifically in the hci_sync component. When the function hci_cmd_sync_queue_once() fails and returns an error, a necessary destroy callback is not called. This results in leaking references or memory because the cleanup process is not properly executed on failure.

Impact Analysis

The impact of this vulnerability is primarily related to resource management. Because memory or references are leaked when the failure occurs, it can lead to increased memory usage and potentially degrade system performance or stability over time. In severe cases, this could cause system crashes or denial of service due to resource exhaustion.

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