CVE-2022-47929: Null Pointer Dereference

Published Jan 9, 2023
·
Updated

A NULL pointer dereference flaw may occur in qdiscgraft in net/sched/schapi.c in the Linux kernel. In this flaw a local unprivileged user mas trigger a denial of service if the allocworkqueue function return is not validated in time of failure. This flaw could allow an attacker to crash the system or leak internal kernel information.

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=96398560f26aa07e8f2969d73c8197e6a6d10407

Other sources

A NULL pointer dereference flaw was found in qdiscgraft in net/sched/schapi.c in the Linux kernel. This issue may allow a local unprivileged user to trigger a denial of service if the allocworkqueue function return is not validated in time of failure, resulting in a system crash or leaked internal kernel information.

In the Linux kernel before 6.1.6, a NULL pointer dereference bug in the traffic control subsystem allows an unprivileged user to trigger a denial of service (system crash) via a crafted traffic control configuration that is set up with "tc qdisc" and "tc class" commands. This affects qdiscgraft in net/sched/schapi.c.

Affected Software

8 affected componentsFixes available
redhat/kernel-rt<0:4.18.0-477.10.1.rt7.274.el8_8
0:4.18.0-477.10.1.rt7.274.el8_8
redhat/kernel<0:4.18.0-477.10.1.el8_8
0:4.18.0-477.10.1.el8_8
redhat/kernel<0:5.14.0-284.11.1.el9_2
0:5.14.0-284.11.1.el9_2
redhat/kernel-rt<0:5.14.0-284.11.1.rt14.296.el9_2
0:5.14.0-284.11.1.rt14.296.el9_2
Linux Linux kernel<6.1.6
Debian Debian Linux=11.0
debian/linux
5.10.223-15.10.234-16.1.129-16.1.135-16.12.25-1
redhat/kernel<6.2
6.2

Remediation

Information

The mitigation is to disable unprivileged user namespaces by setting user.max_user_namespaces to 0: ``` # echo "user.max_user_namespaces=0" > /etc/sysctl.d/userns.conf # sysctl -p /etc/sysctl.d/userns.conf ```

Event History

Jan 9, 2023
CVE Published
05:00 PM
Jan 17, 2023
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
Description
Feb 8, 2023
Data Sourced
via Red Hat·02:59 PM
DescriptionSeverityAffected Software
Jan 12, 2024
Data Sourced
via Launchpad·12:12 AM
Description
May 2, 2025
Data Sourced
via Ubuntu·05:20 AM
RemedyDescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2022-47929?

CVE-2022-47929 has a high severity rating due to its potential to cause a denial of service.

2

How do I fix CVE-2022-47929?

To fix CVE-2022-47929, update to the latest kernel version as specified in the remediation details for your operating system.

3

Who is affected by CVE-2022-47929?

CVE-2022-47929 affects users of vulnerable versions of the Linux kernel, particularly those using the Red Hat and Debian distributions.

4

What type of vulnerability is CVE-2022-47929?

CVE-2022-47929 is a NULL pointer dereference vulnerability that can lead to a system crash.

5

Is there an exploit available for CVE-2022-47929?

While there is no public knowledge of an exploit specifically targeting CVE-2022-47929, the vulnerability does pose significant risk if left unpatched.

Contact

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