CVE-2021-32399: Race Condition

Published May 10, 2021
·
Updated

A flaw was found in the Linux kernel’s handling of the removal of Bluetooth HCI controllers. This flaw allows an attacker with a local account to exploit a race condition, leading to corrupted memory and possible privilege escalation. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

Other sources

net/bluetooth/hcirequest.c in the Linux kernel through 5.12.2 has a race condition for removal of the HCI controller.

Affected Software

51 affected componentsFixes available
redhat/kernel<0:2.6.32-754.43.1.el6
0:2.6.32-754.43.1.el6
redhat/kernel-rt<0:3.10.0-1160.41.1.rt56.1181.el7
0:3.10.0-1160.41.1.rt56.1181.el7
redhat/kernel<0:3.10.0-1160.41.1.el7
0:3.10.0-1160.41.1.el7
redhat/kernel<0:3.10.0-327.100.1.el7
0:3.10.0-327.100.1.el7
redhat/kernel<0:3.10.0-514.92.1.el7
0:3.10.0-514.92.1.el7
redhat/kernel<0:3.10.0-693.94.1.el7
0:3.10.0-693.94.1.el7
redhat/kernel<0:3.10.0-957.80.1.el7
0:3.10.0-957.80.1.el7
redhat/kernel<0:3.10.0-1062.56.1.el7
0:3.10.0-1062.56.1.el7
redhat/kernel-rt<0:4.18.0-305.10.2.rt7.83.el8_4
0:4.18.0-305.10.2.rt7.83.el8_4
redhat/kernel<0:4.18.0-305.10.2.el8_4
0:4.18.0-305.10.2.el8_4
redhat/kernel<0:4.18.0-147.52.1.el8_1
0:4.18.0-147.52.1.el8_1
redhat/kernel-rt<0:4.18.0-193.64.1.rt13.115.el8_2
0:4.18.0-193.64.1.rt13.115.el8_2
redhat/kernel<0:4.18.0-193.64.1.el8_2
0:4.18.0-193.64.1.el8_2
redhat/redhat-virtualization-host<0:4.3.18-20210903.0.el7_9
0:4.3.18-20210903.0.el7_9
redhat/redhat-virtualization-host<0:4.4.7-20210715.1.el8_4
0:4.4.7-20210715.1.el8_4
Linux Linux kernel<=5.12.2
Debian Debian Linux=9.0
NetApp Cloud Backup
All of the following
NetApp Solidfire Baseboard Management Controller Firmware
NetApp Solidfire Baseboard Management Controller
All of the following
NetApp H300s Firmware
NetApp H300s
All of the following
NetApp H500s Firmware
NetApp H500s
All of the following
NetApp H700s Firmware
NetApp H700s
All of the following
NetApp H300e Firmware
NetApp H300e
All of the following
NetApp H500e Firmware
NetApp H500e
All of the following
NetApp H700e Firmware
NetApp H700e
All of the following
NetApp H410s Firmware
NetApp H410s
NetApp Solidfire Baseboard Management Controller Firmware
NetApp Solidfire Baseboard Management Controller
NetApp H300s Firmware
NetApp H300s
NetApp H500s Firmware
NetApp H500s
NetApp H700s Firmware
NetApp H700s
NetApp H300e Firmware
NetApp H300e
NetApp H500e Firmware
NetApp H500e
NetApp H700e Firmware
NetApp H700e
NetApp H410s Firmware
NetApp H410s
debian/linux
5.10.223-15.10.234-16.1.129-16.1.135-16.12.25-16.12.27-1

Remediation

Information

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 the BIOS level which will also provide effective mitigation as the kernel will not be able to detect that Bluetooth hardware is present on the system.

Event History

May 10, 2021
CVE Published
via MITRE·09:19 PM
Data Sourced
via MITRE·09:19 PM
Description
Jun 11, 2021
Data Sourced
via Red Hat·09:22 AM
DescriptionSeverityAffected Software
Jan 11, 2024
Data Sourced
via Launchpad·11:56 PM
Description
Apr 28, 2025
Data Sourced
via Ubuntu·04:30 AM
RemedyDescriptionSeverityAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2021-32399?

CVE-2021-32399 is considered a medium severity vulnerability due to its potential for privilege escalation.

2

How do I fix CVE-2021-32399?

To fix CVE-2021-32399, upgrade to the recommended kernel versions specified by your distribution.

3

What systems are affected by CVE-2021-32399?

CVE-2021-32399 affects various versions of the Linux kernel and specific Red Hat packages.

4

Can CVE-2021-32399 be exploited remotely?

No, CVE-2021-32399 requires a local account for exploitation, limiting its attack surface.

5

What impact does CVE-2021-32399 have on systems?

CVE-2021-32399 can lead to memory corruption and potential privilege escalation, impacting system integrity.

Contact

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