CVE-2021-3669: Medium severity Linux Linux kernel vulnerability

Published Jul 27, 2021
·
Updated

A flaw was found in the Linux kernel. Measuring usage of the shared memory does not scale with large shared memory segment counts which could lead to resource exhaustion and DoS.

Other sources

A flaw was found in the Linux kernel. Reading /proc/sysvipc/shm does not scale with large shared memory segment counts which could lead to resource exhaustion and DoS.

Red Hat

Affected Software

53 affected componentsFixes available
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
Linux Linux kernel
All of the following
Any of the following
IBM Spectrum Copy Data Management>=2.2.0.0<=2.2.15.0
IBM Spectrum Protect Plus>=10.1.0<=10.1.10.2
Linux Linux kernel
Debian Debian Linux=10.0
Debian Debian Linux=11.0
Fedoraproject Fedora=34
redhat Build Of Quarkus>=2.0<2.7
redhat Developer Tools=1.0
redhat Enterprise Linux=6.0
redhat Enterprise Linux=7.0
redhat Enterprise Linux=8.0
redhat Enterprise Linux Aus=8.6
redhat Enterprise Linux For Ibm Z Systems=8.0
redhat Enterprise Linux For Ibm Z Systems Eus=8.6
redhat Enterprise Linux For Power Little Endian=8.0
redhat Enterprise Linux For Power Little Endian Eus=8.6
redhat Enterprise Linux For Real Time=8
redhat Enterprise Linux For Real Time For Nfv=8
redhat Enterprise Linux For Real Time For Nfv Tus=8.6
redhat Enterprise Linux For Real Time Tus=8.6
redhat Enterprise Linux Server Aus=8.6
redhat Enterprise Linux Server For Power Little Endian Update Services For Sap Solutions=8.6
redhat Enterprise Linux Server Tus=8.6
All of the following
redhat Codeready Linux Builder
Any of the following
redhat Enterprise Linux=8.0
redhat Enterprise Linux Eus=8.6
redhat Enterprise Linux For Power Little Endian=8.0
redhat Enterprise Linux For Power Little Endian Eus=8.6
All of the following
Any of the following
redhat OpenShift Container Platform=4.6
redhat OpenShift Container Platform=4.7
redhat OpenShift Container Platform=4.9
redhat Virtualization Host=4.0
redhat Enterprise Linux=8.0
IBM Spectrum Copy Data Management>=2.2.0.0<=2.2.15.0
IBM Spectrum Protect Plus>=10.1.0<=10.1.10.2
Linux Linux kernel
redhat Codeready Linux Builder
redhat Enterprise Linux=8.0
redhat Enterprise Linux Eus=8.6
redhat Enterprise Linux For Power Little Endian=8.0
redhat Enterprise Linux For Power Little Endian Eus=8.6
redhat OpenShift Container Platform=4.6
redhat OpenShift Container Platform=4.7
redhat OpenShift Container Platform=4.9
redhat Virtualization Host=4.0
debian/linux<=5.10.223-1
5.10.244-16.1.148-16.1.158-16.12.57-16.12.48-16.17.8-1
Microsoft azl3 kernel 6.6.35.1-4
Microsoft azl3 kernel 6.6.92.2-1
Microsoft cm1 kernel 5.10.189.1-1
Microsoft cbl2 kernel 5.15.70.1-1

Remediation

Information

Mitigation for this issue is either not available or the currently available options does not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

Event History

Jul 27, 2021
Data Sourced
via Red Hat·04:25 PM
DescriptionSeverityAffected Software
Aug 2, 2021
CVE Published
06:02 AM
Aug 26, 2022
CVE Published
via MITRE·03:25 PM
Data Sourced
via MITRE·03:25 PM
DescriptionWeakness
Data Sourced
via NVD·04:15 PM
DescriptionSeverityWeaknessAffected Software
Aug 30, 2022
Data Sourced
via Microsoft·07:00 AM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·07:00 AM
Affected Software
Updated
via Microsoft·07:00 AM
DescriptionSeverityWeakness
Jan 11, 2024
Data Sourced
via Launchpad·11:58 PM
Description
Apr 28, 2025
Data Sourced
via Ubuntu·04:30 AM
RemedyDescriptionSeverityAffected Software
Nov 21, 2025
Data Sourced
via Debian·10:04 PM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2021-3669?

CVE-2021-3669 has a moderate severity rating as it can lead to resource exhaustion and denial of service in the Linux kernel.

2

How do I fix CVE-2021-3669?

To fix CVE-2021-3669, update the Linux kernel to versions 0:4.18.0-372.9.1.rt7.166.el8 or 0:4.18.0-372.9.1.el8 or later.

3

Which operating systems are affected by CVE-2021-3669?

CVE-2021-3669 affects various Linux distributions including Red Hat Enterprise Linux, Debian, and Fedora.

4

What type of vulnerability is CVE-2021-3669?

CVE-2021-3669 is a denial-of-service (DoS) vulnerability that occurs due to resource exhaustion when handling large shared memory segment counts.

5

Is my Linux system vulnerable to CVE-2021-3669?

You can determine if your Linux system is vulnerable to CVE-2021-3669 by checking if you are running an affected version of the kernel or relevant software.

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