CVE-2025-21827

Published Mar 6, 2025

Last updated 8 days ago

CVSS high 7.8

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btusb: mediatek: Add locks for usb_driver_claim_interface() The documentation for usb_driver_claim_interface() says that "the device lock" is needed when the function is called from places other than probe(). This appears to be the lock for the USB interface device. The Mediatek btusb code gets called via this path: Workqueue: hci0 hci_power_on [bluetooth] Call trace: usb_driver_claim_interface btusb_mtk_claim_iso_intf btusb_mtk_setup hci_dev_open_sync hci_power_on process_scheduled_works worker_thread kthread With the above call trace the device lock hasn't been claimed. Claim it. Without this fix, we'd sometimes see the error "Failed to claim iso interface". Sometimes we'd even see worse errors, like a NULL pointer dereference (where `intf->dev.driver` was NULL) with a trace like: Call trace: usb_suspend_both usb_runtime_suspend __rpm_callback rpm_suspend pm_runtime_work process_scheduled_works Both errors appear to be fixed with the proper locking.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
CWE-667

Social media

Hype score
Not currently trending

  1. (CVE-2025-21827)[Bluetooth][btusb][mediatek]NPD https://t.co/chueMy0cWF

    @xvonfers

    8 Mar 2025

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  2. CVE-2025-21827 In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btusb: mediatek: Add locks for usb_driver_claim_interface() The documentation for usb… https://t.co/fDdCN1A5PJ

    @CVEnew

    7 Mar 2025

    176 Impressions

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  3. CVE-2025-21827 Linux Kernel Bluetooth https://t.co/a9Ulml094c

    @VulmonFeeds

    6 Mar 2025

    6 Impressions

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Configurations

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References

Sources include official advisories and independent security research.