CVE-2021-3573: Race Condition

Published Jun 1, 2021
·
Updated

A flaw use-after-free in function hcisockboundioctl() of the Linux kernel HCI subsystem was found in the way user calls ioct HCIUNBLOCKADDR or other way triggers race condition of the call hciunregisterdev() together with one of the calls hcisockblacklistadd(), hcisockblacklistdel(), hcigetconninfo(), hcigetauthinfo(). A privileged local user could use this flaw to crash the system or escalate their privileges on the system.

Other sources

A use-after-free in function hcisockboundioctl() of the Linux kernel HCI subsystem was found in the way user calls ioct HCIUNBLOCKADDR or other way triggers race condition of the call hciunregisterdev() together with one of the calls hcisockblacklistadd(), hcisockblacklistdel(), hcigetconninfo(), hcigetauthinfo(). A privileged local user could use this flaw to crash the system or escalate their privileges on the system. This flaw affects the Linux kernel versions prior to 5.13-rc5.

A use-after-free vulnerability was found in the Linux kernel in function hcisockboundioctl(). It can allow attackers to corrupt kernel heaps (kmalloc-8k to be specific) and adopt further exploitations.

Red Hat

Affected Software

15 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<5.13
Linux Linux kernel=5.13-rc1
Linux Linux kernel=5.13-rc2
Linux Linux kernel=5.13-rc3
Linux Linux kernel=5.13-rc4
redhat Enterprise Linux=6.0
redhat Enterprise Linux=7.0
redhat Enterprise Linux=8.0
Fedoraproject Fedora=34
redhat/kernel<5.13
5.13
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
  6. Upgrade

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

    Fixed in 5.13
  7. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 5.13-rc5

Event History

Jun 1, 2021
Data Sourced
via Red Hat·12:42 PM
DescriptionSeverityAffected Software
Jun 8, 2021
CVE Published
12:00 AM
Aug 13, 2021
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
DescriptionWeakness
Data Sourced
via NVD·02:15 PM
RemedyDescriptionSeverityWeaknessAffected 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-2021-3573?

CVE-2021-3573 is classified as a high severity vulnerability due to its potential impact on the Linux kernel's HCI subsystem.

2

How do I fix CVE-2021-3573?

To fix CVE-2021-3573, update your Linux kernel to version 0:3.10.0-1160.59.1.el7 or higher, or use the corresponding patched kernel versions for your distribution.

3

What versions of the Linux kernel are affected by CVE-2021-3573?

CVE-2021-3573 affects various versions of the Linux kernel up to 5.13, including specific versions like 3.10.x and 4.18.x.

4

What types of systems are impacted by CVE-2021-3573?

CVE-2021-3573 impacts systems running affected versions of the Linux kernel, such as Red Hat Enterprise Linux, Fedora, and Debian.

5

Is CVE-2021-3573 a zero-day vulnerability?

No, CVE-2021-3573 is not a zero-day vulnerability as it has been publicly disclosed and patches are available.

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