CVE-2021-26931: Medium severity Linux Linux kernel vulnerability

Published Feb 17, 2021
·
Updated

An issue was discovered in the Linux kernel 2.6.39 through 5.10.16, as used in Xen. Block, net, and SCSI backends consider certain errors a plain bug, deliberately causing a kernel crash. For errors potentially being at least under the influence of guests (such as out of memory conditions), it isn't correct to assume a plain bug. Memory allocations potentially causing such crashes occur only when Linux is running in PV mode, though. This affects drivers/block/xen-blkback/blkback.c and drivers/xen/xen-scsiback.c.

Affected Software

86 affected componentsFixes available
Linux Linux kernel>=2.6.39<=5.10.16
Fedoraproject Fedora=32
Fedoraproject Fedora=33
Debian Debian Linux=9.0
debian/linux
5.10.223-15.10.259-16.1.176-16.1.177-16.12.94-16.12.95-17.1.3-17.1.4-1
ubuntu/linux-aws<4.4.0-1090.94
4.4.0-1090.94
ubuntu/linux-azure<4.15.0-1114.127~14.04.1
4.15.0-1114.127~14.04.1
ubuntu/linux-lts-xenial<4.4.0-208.240~14.04.1
4.4.0-208.240~14.04.1
ubuntu/linux*
ubuntu/linux<4.4.0-208.240
4.4.0-208.240
ubuntu/linux-aws<4.4.0-1126.140
4.4.0-1126.140
ubuntu/linux-kvm<4.4.0-1091.100
4.4.0-1091.100
ubuntu/linux-raspi2<4.4.0-1150.161
4.4.0-1150.161
ubuntu/linux-snapdragon<4.4.0-1154.164
4.4.0-1154.164
ubuntu/linux-aws-hwe<4.15.0-1102.109~16.04.1
4.15.0-1102.109~16.04.1
ubuntu/linux-azure<4.15.0-1114.127~16.04.1
4.15.0-1114.127~16.04.1
ubuntu/linux-gcp<4.15.0-1099.112~16.04.1
4.15.0-1099.112~16.04.1
ubuntu/linux-hwe<4.15.0-143.147~16.04.3
4.15.0-143.147~16.04.3
ubuntu/linux-oracle<4.15.0-1071.79~16.04.1
4.15.0-1071.79~16.04.1
ubuntu/linux-hwe-edge*
ubuntu/linux-fips<4.4.0-1060.66
4.4.0-1060.66
ubuntu/linux-fips*
ubuntu/linux<4.15.0-143.147
4.15.0-143.147
ubuntu/linux-aws<4.15.0-1102.109
4.15.0-1102.109
ubuntu/linux-aws-5.4<5.4.0-1043.45~18.04.1
5.4.0-1043.45~18.04.1
ubuntu/linux-azure-4.15<4.15.0-1114.127
4.15.0-1114.127
ubuntu/linux-azure-5.4<5.4.0-1044.46~18.04.1
5.4.0-1044.46~18.04.1
ubuntu/linux-dell300x<4.15.0-1018.22
4.15.0-1018.22
ubuntu/linux-gcp-4.15<4.15.0-1099.112
4.15.0-1099.112
ubuntu/linux-gcp-5.4<5.4.0-1041.44~18.04.1
5.4.0-1041.44~18.04.1
ubuntu/linux-gke-5.4<5.4.0-1040.42~18.04.1
5.4.0-1040.42~18.04.1
ubuntu/linux-gkeop-5.4<5.4.0-1013.14~18.04.1
5.4.0-1013.14~18.04.1
ubuntu/linux-hwe-5.4<5.4.0-71.79~18.04.1
5.4.0-71.79~18.04.1
ubuntu/linux-kvm<4.15.0-1091.93
4.15.0-1091.93
ubuntu/linux-oracle<4.15.0-1071.79
4.15.0-1071.79
ubuntu/linux-oracle-5.4<5.4.0-1042.45~18.04.1
5.4.0-1042.45~18.04.1
ubuntu/linux-raspi-5.4<5.4.0-1033.36~18.04.1
5.4.0-1033.36~18.04.1
ubuntu/linux-raspi2<4.15.0-1085.90
4.15.0-1085.90
ubuntu/linux-snapdragon<4.15.0-1102.111
4.15.0-1102.111
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-hwe*
ubuntu/linux-hwe-edge*
ubuntu/linux-oem*
ubuntu/linux-oracle-5.0*
ubuntu/linux-oracle-5.3*
ubuntu/linux-aws-fips<4.15.0-2044.46
4.15.0-2044.46
ubuntu/linux-azure-fips<4.15.0-2026.29
4.15.0-2026.29
ubuntu/linux-fips<4.15.0-1059.67
4.15.0-1059.67
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux<5.4.0-71.79
5.4.0-71.79
ubuntu/linux-aws<5.4.0-1043.45
5.4.0-1043.45
ubuntu/linux-azure<5.4.0-1044.46
5.4.0-1044.46
ubuntu/linux-gcp<5.4.0-1041.44
5.4.0-1041.44
ubuntu/linux-gke<5.4.0-1041.43
5.4.0-1041.43
ubuntu/linux-gkeop<5.4.0-1013.14
5.4.0-1013.14
ubuntu/linux-hwe-5.8<5.8.0-53.60~20.04.1
5.8.0-53.60~20.04.1
ubuntu/linux-kvm<5.4.0-1037.38
5.4.0-1037.38
ubuntu/linux-oem-5.10<5.10.0-1017.18
5.10.0-1017.18
ubuntu/linux-oracle<5.4.0-1042.45
5.4.0-1042.45
ubuntu/linux-raspi<5.4.0-1033.36
5.4.0-1033.36
ubuntu/linux-riscv-5.8<5.8.0-25.27~20.04.1
5.8.0-25.27~20.04.1
ubuntu/linux-azure-fde-5.15<5.15.0-1114.123~20.04.1
5.15.0-1114.123~20.04.1
ubuntu/linux-oem-5.6*
ubuntu/linux-raspi2*
ubuntu/linux-riscv*
ubuntu/linux-aws-fips<5.4.0-1069.73+fips2
5.4.0-1069.73+fips2
ubuntu/linux-azure-fips<5.4.0-1073.76+fips1
5.4.0-1073.76+fips1
ubuntu/linux-gcp-fips<5.4.0-1067.71~20.04.1
5.4.0-1067.71~20.04.1
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux-intel-iot-realtime*
ubuntu/linux-realtime*
ubuntu/linux-raspi-realtime*
ubuntu/linux-vmware*

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

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

    Fixed in 5.10.223-1Fixed in 5.10.259-1Fixed in 6.1.176-1Fixed in 6.1.177-1Fixed in 6.12.94-1Fixed in 6.12.95-1Fixed in 7.1.3-1Fixed in 7.1.4-1
  2. Upgrade

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

    Fixed in 4.4.0-1090.94
  3. Upgrade

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

    Fixed in 4.15.0-1114.127~14.04.1
  4. Upgrade

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

    Fixed in 4.4.0-208.240~14.04.1
  5. Upgrade

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

    Fixed in 4.4.0-208.240
  6. Upgrade

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

    Fixed in 4.4.0-1126.140
  7. Upgrade

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

    Fixed in 4.4.0-1091.100
  8. Upgrade

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

    Fixed in 4.4.0-1150.161
  9. Upgrade

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

    Fixed in 4.4.0-1154.164
  10. Upgrade

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

    Fixed in 4.15.0-1102.109~16.04.1
  11. Upgrade

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

    Fixed in 4.15.0-1114.127~16.04.1
  12. Upgrade

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

    Fixed in 4.15.0-1099.112~16.04.1
  13. Upgrade

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

    Fixed in 4.15.0-143.147~16.04.3
  14. Upgrade

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

    Fixed in 4.15.0-1071.79~16.04.1
  15. Upgrade

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

    Fixed in 4.4.0-1060.66
  16. Upgrade

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

    Fixed in 4.15.0-143.147
  17. Upgrade

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

    Fixed in 4.15.0-1102.109
  18. Upgrade

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

    Fixed in 5.4.0-1043.45~18.04.1
  19. Upgrade

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

    Fixed in 4.15.0-1114.127
  20. Upgrade

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

    Fixed in 5.4.0-1044.46~18.04.1
  21. Upgrade

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

    Fixed in 4.15.0-1018.22
  22. Upgrade

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

    Fixed in 4.15.0-1099.112
  23. Upgrade

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

    Fixed in 5.4.0-1041.44~18.04.1
  24. Upgrade

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

    Fixed in 5.4.0-1040.42~18.04.1
  25. Upgrade

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

    Fixed in 5.4.0-1013.14~18.04.1
  26. Upgrade

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

    Fixed in 5.4.0-71.79~18.04.1
  27. Upgrade

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

    Fixed in 4.15.0-1091.93
  28. Upgrade

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

    Fixed in 4.15.0-1071.79
  29. Upgrade

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

    Fixed in 5.4.0-1042.45~18.04.1
  30. Upgrade

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

    Fixed in 5.4.0-1033.36~18.04.1
  31. Upgrade

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

    Fixed in 4.15.0-1085.90
  32. Upgrade

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

    Fixed in 4.15.0-1102.111
  33. Upgrade

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

    Fixed in 4.15.0-2044.46
  34. Upgrade

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

    Fixed in 4.15.0-2026.29
  35. Upgrade

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

    Fixed in 4.15.0-1059.67
  36. Upgrade

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

    Fixed in 5.4.0-71.79
  37. Upgrade

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

    Fixed in 5.4.0-1043.45
  38. Upgrade

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

    Fixed in 5.4.0-1044.46
  39. Upgrade

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

    Fixed in 5.4.0-1041.44
  40. Upgrade

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

    Fixed in 5.4.0-1041.43
  41. Upgrade

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

    Fixed in 5.4.0-1013.14
  42. Upgrade

    Upgrade ubuntu/linux-hwe-5.8 to a version that resolves this vulnerability.

    Fixed in 5.8.0-53.60~20.04.1
  43. Upgrade

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

    Fixed in 5.4.0-1037.38
  44. Upgrade

    Upgrade ubuntu/linux-oem-5.10 to a version that resolves this vulnerability.

    Fixed in 5.10.0-1017.18
  45. Upgrade

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

    Fixed in 5.4.0-1042.45
  46. Upgrade

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

    Fixed in 5.4.0-1033.36
  47. Upgrade

    Upgrade ubuntu/linux-riscv-5.8 to a version that resolves this vulnerability.

    Fixed in 5.8.0-25.27~20.04.1
  48. Upgrade

    Upgrade ubuntu/linux-azure-fde-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1114.123~20.04.1
  49. Upgrade

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

    Fixed in 5.4.0-1069.73+fips2
  50. Upgrade

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

    Fixed in 5.4.0-1073.76+fips1
  51. Upgrade

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

    Fixed in 5.4.0-1067.71~20.04.1

Event History

Feb 17, 2021
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
Description
Data Sourced
via OSV·02:15 AM
DescriptionSeverityAffected Software
Data Sourced
via NVD·02:15 AM
RemedyDescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2021-26931?

CVE-2021-26931 is classified as a high severity vulnerability due to its potential to cause kernel crashes.

2

How do I fix CVE-2021-26931?

To fix CVE-2021-26931, update your Linux kernel to version 5.10.223-1, 5.10.226-1, 6.1.123-1, 6.1.119-1, or 6.12.10-1, depending on your distribution.

3

Which versions of the Linux kernel are affected by CVE-2021-26931?

CVE-2021-26931 affects Linux kernel versions from 2.6.39 to 5.10.16.

4

What systems are vulnerable to CVE-2021-26931?

Systems running certain versions of the Linux kernel, Fedora 32 and 33, and Debian 9.0 are vulnerable to CVE-2021-26931.

5

Is there a workaround for CVE-2021-26931?

There is no specific workaround for CVE-2021-26931, and the recommended action is to apply the available updates.

Company

Resources

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