CVE-2021-3564
kernel: double free in bluetooth subsystem when the HCI device initialization fails
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · May 25, 2021
Updated · June 28, 2026
Description
A flaw double-free memory corruption in the Linux kernel HCI device initialization subsystem was found in the way user attach malicious HCI TTY Bluetooth device. A local user could use this flaw to crash the system.
Statement
The impact is Moderate, because the double free happens during flush procedure, and no use of incorrect data during flush finishing even if double free could happen without kernel crash.
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 don't 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 · 6.3CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H
CWE-415 · Double Free