CVE-2021-34981

2021-11-0105:49:19

redhat.com

access.redhat.com

CVSS3

7.5

Attack Vector

LOCAL

Attack Complexity

HIGH

Privileges Required

HIGH

User Interaction

NONE

Scope

CHANGED

Confidentiality Impact

HIGH

Integrity Impact

HIGH

Availability Impact

HIGH

CVSS:3.0/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H

EPSS

0.001

Percentile

28.8%

JSON

A flaw was found in the Linux kernel’s CAPI over Bluetooth connection code. An attacker with a local account can escalate privileges when CAPI (ISDN) hardware connection fails.

Mitigation

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.