CVE-2021-3564: Double Free

Published May 24, 2021
·
Updated

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.

Other sources

A flaw was found in the Linux kernel in the BlueTooth subsystem when the HCI device initialization fails. It can lead to unexpected results, like double-free memory corruption vulnerability.

— Red Hat

Affected Software

8 affected componentsFixes available
redhat/kernel-rt<0:3.10.0-1160.59.1.rt56.1200.el7
0:3.10.0-1160.59.1.rt56.1200.el7
redhat/kernel<0:3.10.0-1160.59.1.el7
0:3.10.0-1160.59.1.el7
redhat/kernel-rt<0:4.18.0-348.rt7.130.el8
0:4.18.0-348.rt7.130.el8
redhat/kernel<0:4.18.0-348.el8
0:4.18.0-348.el8
Linux Linux kernel>=3.13
Fedoraproject Fedora=34
Debian Debian Linux=9.0
debian/linux
5.10.223-15.10.234-16.1.129-16.1.135-16.12.25-16.12.27-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade redhat/kernel-rt to a version that resolves this vulnerability.

    Fixed in 0:3.10.0-1160.59.1.rt56.1200.el7
  2. Upgrade

    Upgrade redhat/kernel to a version that resolves this vulnerability.

    Fixed in 0:3.10.0-1160.59.1.el7
  3. Upgrade

    Upgrade redhat/kernel-rt to a version that resolves this vulnerability.

    Fixed in 0:4.18.0-348.rt7.130.el8
  4. Upgrade

    Upgrade redhat/kernel to a version that resolves this vulnerability.

    Fixed in 0:4.18.0-348.el8
  5. Upgrade

    Upgrade debian/linux to a version that resolves this vulnerability.

    Fixed in 5.10.223-1Fixed in 5.10.234-1Fixed in 6.1.129-1Fixed in 6.1.135-1Fixed in 6.12.25-1Fixed in 6.12.27-1

Event History

May 24, 2021
Data Sourced
via Red Hat·07:31 PM
DescriptionSeverityAffected Software
May 25, 2021
CVE Published
12:00 AM
Jun 8, 2021
CVE Published
via MITRE·11:59 AM
Data Sourced
via MITRE·11:59 AM
DescriptionWeakness
Data Sourced
via NVD·12:15 PM
DescriptionSeverityWeaknessAffected Software
Jan 11, 2024
Data Sourced
via Launchpad·11:57 PM
Description
Apr 28, 2025
Data Sourced
via Ubuntu·04:30 AM
RemedyDescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2021-3564?

CVE-2021-3564 has been classified as a high severity vulnerability due to its potential to cause system crashes.

2

How do I fix CVE-2021-3564?

To resolve CVE-2021-3564, ensure that your Linux kernel is updated to the versions specified by your distribution's security advisories.

3

Who is affected by CVE-2021-3564?

CVE-2021-3564 affects local users of systems running vulnerable versions of the Linux kernel that allow for HCI Bluetooth device initialization.

4

Can CVE-2021-3564 be exploited remotely?

CVE-2021-3564 requires local access to the system, as it involves user-initiated actions that can lead to a crash.

5

What types of Linux distributions are impacted by CVE-2021-3564?

CVE-2021-3564 affects several Linux distributions including Red Hat, Fedora, and Debian, depending on the kernel version.

Company

Resources

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