7.8
CWE
287
Advisory Published
CVE Published
Updated

CVE-2021-4197

First published: Sun Sep 12 2021(Updated: )

An unprivileged write to the file handler flaw in the Linux kernel's control groups and namespaces subsystem was found in the way users have access to some less privileged process that are controlled by cgroups and have higher privileged parent process. It is actually both for cgroup2 and cgroup1 versions of control groups. A local user could use this flaw to crash the system or escalate their privileges on the system.

Credit: secalert@redhat.com

Affected SoftwareAffected VersionHow to fix
redhat/kernel-rt<0:4.18.0-372.9.1.rt7.166.el8
0:4.18.0-372.9.1.rt7.166.el8
redhat/kernel<0:4.18.0-372.9.1.el8
0:4.18.0-372.9.1.el8
redhat/kernel-rt<0:4.18.0-305.57.1.rt7.129.el8_4
0:4.18.0-305.57.1.rt7.129.el8_4
redhat/kernel<0:4.18.0-305.57.1.el8_4
0:4.18.0-305.57.1.el8_4
redhat/Linux kernel<5.17
5.17
Linux Kernel>=4.2<4.14.276
Linux Kernel>=4.15<4.19.238
Linux Kernel>=4.20<5.4.189
Linux Kernel>=5.5<5.10.111
Linux Kernel>=5.11<5.15.14
oracle communications Cloud native core binding support function=22.1.1
oracle communications Cloud native core binding support function=22.1.3
oracle communications Cloud native core binding support function=22.2.0
Debian GNU/Linux=10.0
broadcom brocade fabric operating system firmware
All of
netapp h300s firmware
netapp h300s
All of
NetApp H500S Firmware
netapp h500s
All of
netapp h700s firmware
netapp h700s
All of
netapp h410s firmware
netapp h410s
All of
netapp h410c firmware
netapp h410c
netapp h300s firmware
netapp h300s
NetApp H500S Firmware
netapp h500s
netapp h700s firmware
netapp h700s
netapp h410s firmware
netapp h410s
netapp h410c firmware
netapp h410c
debian/linux
5.10.223-1
5.10.226-1
6.1.123-1
6.1.128-1
6.12.12-1
6.12.15-1

Remedy

The mitigation not known. However, for the default configuration of the Red Hat Enterprise Linux it is not possible to trigger this vulnerability: if control groups (cgroups) not being used or being used with the default configuration or being used some other configuration where for example similar privileges for all processes (both for parent and for child processes), then no way to trigger this vulnerability.

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Parent vulnerabilities

(Appears in the following advisories)

Frequently Asked Questions

  • What is the severity of CVE-2021-4197?

    CVE-2021-4197 has a high severity rating due to the potential for unprivileged users to write to file handlers controlled by cgroups.

  • What versions of the Linux kernel are affected by CVE-2021-4197?

    CVE-2021-4197 affects Linux kernel versions up to 4.18.0-372.9.1 and various versions within the 4.x series up to 5.x.

  • How do I fix CVE-2021-4197?

    To fix CVE-2021-4197, update your Linux kernel to the specified remedied versions for your distribution as indicated in the security advisories.

  • Can CVE-2021-4197 be exploited remotely?

    CVE-2021-4197 requires local access to exploit, which means it cannot be directly exploited remotely.

  • What are the potential impacts of CVE-2021-4197?

    The potential impacts of CVE-2021-4197 include unauthorized access to file handlers and potential privilege escalation for unprivileged processes.

Contact

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