CVE-2022-3564

A use-after-free flaw was found in the Linux kernel’s L2CAP bluetooth functionality in how a user triggers a race condition by two malicious flows in the L2CAP bluetooth packets. This flaw allows a local or bluetooth connection user to crash the system or potentially escalate privileges.

This issue is rated between Moderate and Important (similar to the CVE-2022-45934) because of no known attack, and the attack would be complex. Anyway, consider this CVE-2022-3564 as Important because the use-after-free can potentially lead to privilege escalation or a potential remote system crash (and currently, a read after-free that in most cases would not lead to a remote system crash).

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.

To mitigate these vulnerabilities on the operating system level, disable the Bluetooth functionality via blocklisting kernel modules in the Linux kernel. The kernel modules can be prevented from being loaded by using system-wide modprobe rules. Instructions on how to disable Bluetooth modules are available on the Customer Portal at https://access.redhat.com/solutions/2682931.

Alternatively, Bluetooth can be disabled within the hardware or at BIOS level which will also provide an effective mitigation as the kernel will not be able to detect that Bluetooth hardware is present on the system.