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

155 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
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
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
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
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
Microsoft azl3 kernel 6.6.35.1-4
Patch available
Microsoft cm1 kernel 5.10.189.1-1
Patch available
Microsoft azl3 kernel 6.6.92.2-1
Patch available
Microsoft cbl2 kernel 5.15.70.1-1
Patch available
ubuntu/linux-aws<4.4.0-1117.123
4.4.0-1117.123
ubuntu/linux-azure<4.15.0-1162.177~14.04.1
4.15.0-1162.177~14.04.1
ubuntu/linux-lts-xenial<4.4.0-239.273~14.04.1
4.4.0-239.273~14.04.1
ubuntu/linux*
ubuntu/linux<4.4.0-239.273
4.4.0-239.273
ubuntu/linux-aws<4.4.0-1155.170
4.4.0-1155.170
ubuntu/linux-aws-hwe<4.15.0-1153.166~16.04.1
4.15.0-1153.166~16.04.1
ubuntu/linux-azure<4.15.0-1162.177~16.04.1
4.15.0-1162.177~16.04.1
ubuntu/linux-gcp<4.15.0-1147.163~16.04.1
4.15.0-1147.163~16.04.1
ubuntu/linux-hwe<4.15.0-208.219~16.04.1
4.15.0-208.219~16.04.1
ubuntu/linux-kvm<4.4.0-1118.128
4.4.0-1118.128
ubuntu/linux-oracle<4.15.0-1116.127~16.04.1
4.15.0-1116.127~16.04.1
ubuntu/linux-hwe-edge*
ubuntu/linux-fips<4.4.0-1088.95
4.4.0-1088.95
ubuntu/linux-fips*
ubuntu/linux<4.15.0-208.220
4.15.0-208.220
ubuntu/linux-aws<4.15.0-1153.166
4.15.0-1153.166
ubuntu/linux-aws-5.4<5.4.0-1099.107~18.04.1
5.4.0-1099.107~18.04.1
ubuntu/linux-azure-4.15<4.15.0-1162.177
4.15.0-1162.177
ubuntu/linux-azure-5.4<5.4.0-1105.111~18.04.1
5.4.0-1105.111~18.04.1
ubuntu/linux-dell300x<4.15.0-1062.67
4.15.0-1062.67
ubuntu/linux-gcp-4.15<4.15.0-1147.163
4.15.0-1147.163
ubuntu/linux-gcp-5.4<5.4.0-1102.111~18.04.2
5.4.0-1102.111~18.04.2
ubuntu/linux-hwe-5.4<5.4.0-146.163~18.04.1
5.4.0-146.163~18.04.1
ubuntu/linux-ibm-5.4<5.4.0-1046.51~18.04.1
5.4.0-1046.51~18.04.1
ubuntu/linux-kvm<4.15.0-1137.142
4.15.0-1137.142
ubuntu/linux-oracle<4.15.0-1116.127
4.15.0-1116.127
ubuntu/linux-oracle-5.4<5.4.0-1098.107~18.04.1
5.4.0-1098.107~18.04.1
ubuntu/linux-raspi-5.4<5.4.0-1082.93~18.04.1
5.4.0-1082.93~18.04.1
ubuntu/linux-raspi2<4.15.0-1129.137
4.15.0-1129.137
ubuntu/linux-snapdragon<4.15.0-1148.158
4.15.0-1148.158
ubuntu/linux-aws-5.0*
ubuntu/linux-aws-5.3*
ubuntu/linux-azure*
ubuntu/linux-azure-5.3*
ubuntu/linux-azure-edge*
ubuntu/linux-gcp*
ubuntu/linux-gcp-5.3*
ubuntu/linux-gcp-edge*
ubuntu/linux-gke-4.15*
ubuntu/linux-gke-5.4*
ubuntu/linux-gkeop-5.4*
ubuntu/linux-hwe*
ubuntu/linux-hwe-edge*
ubuntu/linux-oem*
ubuntu/linux-oracle-5.0*
ubuntu/linux-oracle-5.3*
ubuntu/linux-aws-fips<4.15.0-2092.98
4.15.0-2092.98
ubuntu/linux-azure-fips<4.15.0-2071.77
4.15.0-2071.77
ubuntu/linux-fips<4.15.0-1108.119
4.15.0-1108.119
ubuntu/linux-gcp-fips<4.15.0-2055.60
4.15.0-2055.60
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux<5.4.0-146.163
5.4.0-146.163
ubuntu/linux-aws<5.4.0-1099.107
5.4.0-1099.107
ubuntu/linux-azure<5.4.0-1105.111
5.4.0-1105.111
ubuntu/linux-bluefield<5.4.0-1060.66
5.4.0-1060.66
ubuntu/linux-gcp<5.4.0-1102.111
5.4.0-1102.111
ubuntu/linux-gke<5.4.0-1096.103
5.4.0-1096.103
ubuntu/linux-gkeop<5.4.0-1066.70
5.4.0-1066.70
ubuntu/linux-ibm<5.4.0-1046.51
5.4.0-1046.51
ubuntu/linux-iot<5.4.0-1013.15
5.4.0-1013.15
ubuntu/linux-kvm<5.4.0-1088.94
5.4.0-1088.94
ubuntu/linux-oracle<5.4.0-1098.107
5.4.0-1098.107
ubuntu/linux-raspi<5.4.0-1082.93
5.4.0-1082.93
ubuntu/linux-xilinx-zynqmp<5.4.0-1023.27
5.4.0-1023.27
ubuntu/linux-aws-5.11*
ubuntu/linux-aws-5.13*
ubuntu/linux-aws-5.8*
ubuntu/linux-azure-5.11*
ubuntu/linux-azure-5.13*
ubuntu/linux-azure-5.8*
ubuntu/linux-gcp-5.11*
ubuntu/linux-gcp-5.13*
ubuntu/linux-gcp-5.8*
ubuntu/linux-hwe-5.11*
ubuntu/linux-hwe-5.13*
ubuntu/linux-hwe-5.8*
ubuntu/linux-intel-5.13*
ubuntu/linux-oem-5.10*
ubuntu/linux-oem-5.13*
ubuntu/linux-oem-5.6*
ubuntu/linux-oracle-5.11*
ubuntu/linux-oracle-5.13*
ubuntu/linux-oracle-5.8*
ubuntu/linux-raspi2*
ubuntu/linux-riscv*
ubuntu/linux-riscv-5.11*
ubuntu/linux-riscv-5.8*
ubuntu/linux-aws-fips<5.4.0-1099.107+fips1
5.4.0-1099.107+fips1
ubuntu/linux-azure-fips<5.4.0-1105.111+fips1
5.4.0-1105.111+fips1
ubuntu/linux-fips<5.4.0-1074.83
5.4.0-1074.83
ubuntu/linux-gcp-fips<5.4.0-1102.111+fips1
5.4.0-1102.111+fips1
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux-intel-iot-realtime*
ubuntu/linux-realtime*
ubuntu/linux-raspi-realtime*
debian/linux
6.1.176-16.1.190-16.12.107-16.12.116-17.2.15-17.3.3-1

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 0:4.18.0-372.9.1.rt7.166.el8
  2. Upgrade

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

    Fixed in 0:4.18.0-372.9.1.el8
  3. Upgrade

    Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.

    Fixed in 4.4.0-1117.123
  4. Upgrade

    Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.

    Fixed in 4.15.0-1162.177~14.04.1
  5. Upgrade

    Upgrade ubuntu/linux-lts-xenial to a version that resolves this vulnerability.

    Fixed in 4.4.0-239.273~14.04.1
  6. Upgrade

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

    Fixed in 4.4.0-239.273
  7. Upgrade

    Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.

    Fixed in 4.4.0-1155.170
  8. Upgrade

    Upgrade ubuntu/linux-aws-hwe to a version that resolves this vulnerability.

    Fixed in 4.15.0-1153.166~16.04.1
  9. Upgrade

    Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.

    Fixed in 4.15.0-1162.177~16.04.1
  10. Upgrade

    Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.

    Fixed in 4.15.0-1147.163~16.04.1
  11. Upgrade

    Upgrade ubuntu/linux-hwe to a version that resolves this vulnerability.

    Fixed in 4.15.0-208.219~16.04.1
  12. Upgrade

    Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.

    Fixed in 4.4.0-1118.128
  13. Upgrade

    Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.

    Fixed in 4.15.0-1116.127~16.04.1
  14. Upgrade

    Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.

    Fixed in 4.4.0-1088.95
  15. Upgrade

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

    Fixed in 4.15.0-208.220
  16. Upgrade

    Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.

    Fixed in 4.15.0-1153.166
  17. Upgrade

    Upgrade ubuntu/linux-aws-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-1099.107~18.04.1
  18. Upgrade

    Upgrade ubuntu/linux-azure-4.15 to a version that resolves this vulnerability.

    Fixed in 4.15.0-1162.177
  19. Upgrade

    Upgrade ubuntu/linux-azure-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-1105.111~18.04.1
  20. Upgrade

    Upgrade ubuntu/linux-dell300x to a version that resolves this vulnerability.

    Fixed in 4.15.0-1062.67
  21. Upgrade

    Upgrade ubuntu/linux-gcp-4.15 to a version that resolves this vulnerability.

    Fixed in 4.15.0-1147.163
  22. Upgrade

    Upgrade ubuntu/linux-gcp-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-1102.111~18.04.2
  23. Upgrade

    Upgrade ubuntu/linux-hwe-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-146.163~18.04.1
  24. Upgrade

    Upgrade ubuntu/linux-ibm-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-1046.51~18.04.1
  25. Upgrade

    Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.

    Fixed in 4.15.0-1137.142
  26. Upgrade

    Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.

    Fixed in 4.15.0-1116.127
  27. Upgrade

    Upgrade ubuntu/linux-oracle-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-1098.107~18.04.1
  28. Upgrade

    Upgrade ubuntu/linux-raspi-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-1082.93~18.04.1
  29. Upgrade

    Upgrade ubuntu/linux-raspi2 to a version that resolves this vulnerability.

    Fixed in 4.15.0-1129.137
  30. Upgrade

    Upgrade ubuntu/linux-snapdragon to a version that resolves this vulnerability.

    Fixed in 4.15.0-1148.158
  31. Upgrade

    Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.

    Fixed in 4.15.0-2092.98
  32. Upgrade

    Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.

    Fixed in 4.15.0-2071.77
  33. Upgrade

    Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.

    Fixed in 4.15.0-1108.119
  34. Upgrade

    Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.

    Fixed in 4.15.0-2055.60
  35. Upgrade

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

    Fixed in 5.4.0-146.163
  36. Upgrade

    Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.

    Fixed in 5.4.0-1099.107
  37. Upgrade

    Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.

    Fixed in 5.4.0-1105.111
  38. Upgrade

    Upgrade ubuntu/linux-bluefield to a version that resolves this vulnerability.

    Fixed in 5.4.0-1060.66
  39. Upgrade

    Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.

    Fixed in 5.4.0-1102.111
  40. Upgrade

    Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.

    Fixed in 5.4.0-1096.103
  41. Upgrade

    Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.

    Fixed in 5.4.0-1066.70
  42. Upgrade

    Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.

    Fixed in 5.4.0-1046.51
  43. Upgrade

    Upgrade ubuntu/linux-iot to a version that resolves this vulnerability.

    Fixed in 5.4.0-1013.15
  44. Upgrade

    Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.

    Fixed in 5.4.0-1088.94
  45. Upgrade

    Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.

    Fixed in 5.4.0-1098.107
  46. Upgrade

    Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.

    Fixed in 5.4.0-1082.93
  47. Upgrade

    Upgrade ubuntu/linux-xilinx-zynqmp to a version that resolves this vulnerability.

    Fixed in 5.4.0-1023.27
  48. Upgrade

    Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.

    Fixed in 5.4.0-1099.107+fips1
  49. Upgrade

    Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.

    Fixed in 5.4.0-1105.111+fips1
  50. Upgrade

    Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.

    Fixed in 5.4.0-1074.83
  51. Upgrade

    Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.

    Fixed in 5.4.0-1102.111+fips1
  52. Upgrade

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

    Fixed in 6.1.176-1Fixed in 6.1.190-1Fixed in 6.12.107-1Fixed in 6.12.116-1Fixed in 7.2.15-1Fixed in 7.3.3-1

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
Data Sourced
via Ubuntu·12:00 AM
RemedyDescriptionSeverityAffected Software
CVE Published
via MITRE·03:25 PM
Data Sourced
via MITRE·03:25 PM
DescriptionWeakness
Data Sourced
via OSV·04:15 PM
DescriptionSeverityAffected Software
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

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

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.

Company

Resources

Contact

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