CVE-2025-71082: Bluetooth: btusb: revert use of devm_kzalloc in btusb

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-01-13 · updated 2026-10-19
Weakness: CWE-416

Description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btusb: revert use of devm_kzalloc in btusb This reverts commit 98921dbd00c4e ("Bluetooth: Use devm_kzalloc in btusb.c file"). In btusb_probe(), we use devm_kzalloc() to allocate the btusb data. This ties the lifetime of all the btusb data to the binding of a driver to one interface, INTF. In a driver that binds to other interfaces, ISOC and DIAG, this is an accident waiting to happen. The issue is revealed in btusb_disconnect(), where calling usb_driver_release_interface(&btusb_driver, data->intf) will have devm free the data that is also being used by the other interfaces of the driver that may not be released yet. To fix this, revert the use of devm and go back to freeing memory explicitly.

Affected products

Linux kernel: from 3.7.1 before 5.15.198; from 5.16 before 6.1.160; from 6.2 before 6.6.120; from 6.7 before 6.12.64; from 6.13 before 6.18.4; 3.7, 6.19-rc1, 6.19-rc2, 6.19-rc3, 6.19-rc4, 6.19-rc5 (+3) — fixed in 5.15.198, 6.1.160, 6.12.64, 6.18.4, 6.6.120

How to fix

Upgrade to a fixed version: Linux kernel 5.15.198, 6.1.160, 6.12.64, 6.18.4. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2025-71082 or the next vulnerability affects your stack