CVE-2021-34693: Medium severity Linux Linux kernel vulnerability

Published Jun 14, 2021
·
Updated

Last updated 25 April 2025

Other sources

net/can/bcm.c in the Linux kernel through 5.12.10 allows local users to obtain sensitive information from kernel stack memory because parts of a data structure are uninitialized.

— Launchpad

Affected Software

96 affected componentsFixes available
Linux Linux kernel>=2.6.25<=5.12.10
Debian Debian Linux=9.0
Debian Debian Linux=10.0
debian/linux
5.10.223-15.10.234-16.1.129-16.1.135-16.12.25-16.12.27-1
ubuntu/linux-aws<4.4.0-1099.104
4.4.0-1099.104
ubuntu/linux-azure<4.15.0-1123.136~14.04.1
4.15.0-1123.136~14.04.1
ubuntu/linux-lts-xenial<4.4.0-219.252~14.04.1
4.4.0-219.252~14.04.1
ubuntu/linux*
ubuntu/linux<4.4.0-219.252
4.4.0-219.252
ubuntu/linux-aws<4.4.0-1135.149
4.4.0-1135.149
ubuntu/linux-aws-hwe<4.15.0-1111.118~16.04.1
4.15.0-1111.118~16.04.1
ubuntu/linux-azure<4.15.0-1123.136~16.04.1
4.15.0-1123.136~16.04.1
ubuntu/linux-gcp<4.15.0-1108.122~16.04.1
4.15.0-1108.122~16.04.1
ubuntu/linux-hwe<4.15.0-156.163~16.04.1
4.15.0-156.163~16.04.1
ubuntu/linux-kvm<4.4.0-1100.109
4.4.0-1100.109
ubuntu/linux-oracle<4.15.0-1080.88~16.04.1
4.15.0-1080.88~16.04.1
ubuntu/linux-hwe-edge*
ubuntu/linux-fips<4.4.0-1069.75
4.4.0-1069.75
ubuntu/linux-fips*
ubuntu/linux<4.15.0-156.163
4.15.0-156.163
ubuntu/linux-aws<4.15.0-1111.118
4.15.0-1111.118
ubuntu/linux-aws-5.4<5.4.0-1055.58~18.04.1
5.4.0-1055.58~18.04.1
ubuntu/linux-azure-4.15<4.15.0-1123.136
4.15.0-1123.136
ubuntu/linux-azure-5.4<5.4.0-1056.58~18.04.1
5.4.0-1056.58~18.04.1
ubuntu/linux-dell300x<4.15.0-1027.32
4.15.0-1027.32
ubuntu/linux-gcp-4.15<4.15.0-1108.122
4.15.0-1108.122
ubuntu/linux-gcp-5.4<5.4.0-1051.55~18.04.1
5.4.0-1051.55~18.04.1
ubuntu/linux-gke-5.4<5.4.0-1051.54~18.04.1
5.4.0-1051.54~18.04.1
ubuntu/linux-gkeop-5.4<5.4.0-1022.23~18.04.1
5.4.0-1022.23~18.04.1
ubuntu/linux-hwe-5.4<5.4.0-81.91~18.04.1
5.4.0-81.91~18.04.1
ubuntu/linux-kvm<4.15.0-1099.101
4.15.0-1099.101
ubuntu/linux-oracle<4.15.0-1080.88
4.15.0-1080.88
ubuntu/linux-oracle-5.4<5.4.0-1053.57~18.04.1
5.4.0-1053.57~18.04.1
ubuntu/linux-raspi-5.4<5.4.0-1042.46~18.04.3
5.4.0-1042.46~18.04.3
ubuntu/linux-raspi2<4.15.0-1095.101
4.15.0-1095.101
ubuntu/linux-snapdragon<4.15.0-1112.121
4.15.0-1112.121
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<4.15.0-2053.55
4.15.0-2053.55
ubuntu/linux-azure-fips<4.15.0-2035.39
4.15.0-2035.39
ubuntu/linux-fips<4.15.0-1069.78
4.15.0-1069.78
ubuntu/linux-gcp-fips<4.15.0-2018.20
4.15.0-2018.20
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux<5.4.0-81.91
5.4.0-81.91
ubuntu/linux-aws<5.4.0-1055.58
5.4.0-1055.58
ubuntu/linux-aws-5.11<5.11.0-1017.18~20.04.1
5.11.0-1017.18~20.04.1
ubuntu/linux-azure<5.4.0-1056.58
5.4.0-1056.58
ubuntu/linux-azure-5.11<5.11.0-1015.16~20.04.1
5.11.0-1015.16~20.04.1
ubuntu/linux-bluefield<5.4.0-1019.22
5.4.0-1019.22
ubuntu/linux-gcp<5.4.0-1051.55
5.4.0-1051.55
ubuntu/linux-gcp-5.11<5.11.0-1018.20~20.04.2
5.11.0-1018.20~20.04.2
ubuntu/linux-gke<5.4.0-1051.54
5.4.0-1051.54
ubuntu/linux-gkeop<5.4.0-1022.23
5.4.0-1022.23
ubuntu/linux-hwe-5.11<5.11.0-34.36~20.04.1
5.11.0-34.36~20.04.1
ubuntu/linux-kvm<5.4.0-1045.47
5.4.0-1045.47
ubuntu/linux-oem-5.10<5.10.0-1038.40
5.10.0-1038.40
ubuntu/linux-oracle<5.4.0-1053.57
5.4.0-1053.57
ubuntu/linux-oracle-5.11<5.11.0-1017.18~20.04.1
5.11.0-1017.18~20.04.1
ubuntu/linux-raspi<5.4.0-1042.46
5.4.0-1042.46
ubuntu/linux-riscv-5.11<5.11.0-1018.19~20.04.2
5.11.0-1018.19~20.04.2
ubuntu/linux-aws-5.8*
ubuntu/linux-azure-5.8*
ubuntu/linux-gcp-5.8*
ubuntu/linux-hwe-5.8*
ubuntu/linux-oem-5.6*
ubuntu/linux-oracle-5.8*
ubuntu/linux-raspi2*
ubuntu/linux-riscv*
ubuntu/linux-riscv-5.8*
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-fips<5.4.0-1032.37
5.4.0-1032.37
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-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 5.10.234-1Fixed in 6.1.129-1Fixed in 6.1.135-1Fixed in 6.12.25-1Fixed in 6.12.27-1
  2. Upgrade

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

    Fixed in 4.4.0-1099.104
  3. Upgrade

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

    Fixed in 4.15.0-1123.136~14.04.1
  4. Upgrade

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

    Fixed in 4.4.0-219.252~14.04.1
  5. Upgrade

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

    Fixed in 4.4.0-219.252
  6. Upgrade

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

    Fixed in 4.4.0-1135.149
  7. Upgrade

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

    Fixed in 4.15.0-1111.118~16.04.1
  8. Upgrade

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

    Fixed in 4.15.0-1123.136~16.04.1
  9. Upgrade

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

    Fixed in 4.15.0-1108.122~16.04.1
  10. Upgrade

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

    Fixed in 4.15.0-156.163~16.04.1
  11. Upgrade

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

    Fixed in 4.4.0-1100.109
  12. Upgrade

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

    Fixed in 4.15.0-1080.88~16.04.1
  13. Upgrade

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

    Fixed in 4.4.0-1069.75
  14. Upgrade

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

    Fixed in 4.15.0-156.163
  15. Upgrade

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

    Fixed in 4.15.0-1111.118
  16. Upgrade

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

    Fixed in 5.4.0-1055.58~18.04.1
  17. Upgrade

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

    Fixed in 4.15.0-1123.136
  18. Upgrade

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

    Fixed in 5.4.0-1056.58~18.04.1
  19. Upgrade

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

    Fixed in 4.15.0-1027.32
  20. Upgrade

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

    Fixed in 4.15.0-1108.122
  21. Upgrade

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

    Fixed in 5.4.0-1051.55~18.04.1
  22. Upgrade

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

    Fixed in 5.4.0-1051.54~18.04.1
  23. Upgrade

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

    Fixed in 5.4.0-1022.23~18.04.1
  24. Upgrade

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

    Fixed in 5.4.0-81.91~18.04.1
  25. Upgrade

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

    Fixed in 4.15.0-1099.101
  26. Upgrade

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

    Fixed in 4.15.0-1080.88
  27. Upgrade

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

    Fixed in 5.4.0-1053.57~18.04.1
  28. Upgrade

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

    Fixed in 5.4.0-1042.46~18.04.3
  29. Upgrade

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

    Fixed in 4.15.0-1095.101
  30. Upgrade

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

    Fixed in 4.15.0-1112.121
  31. Upgrade

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

    Fixed in 4.15.0-2053.55
  32. Upgrade

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

    Fixed in 4.15.0-2035.39
  33. Upgrade

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

    Fixed in 4.15.0-1069.78
  34. Upgrade

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

    Fixed in 4.15.0-2018.20
  35. Upgrade

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

    Fixed in 5.4.0-81.91
  36. Upgrade

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

    Fixed in 5.4.0-1055.58
  37. Upgrade

    Upgrade ubuntu/linux-aws-5.11 to a version that resolves this vulnerability.

    Fixed in 5.11.0-1017.18~20.04.1
  38. Upgrade

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

    Fixed in 5.4.0-1056.58
  39. Upgrade

    Upgrade ubuntu/linux-azure-5.11 to a version that resolves this vulnerability.

    Fixed in 5.11.0-1015.16~20.04.1
  40. Upgrade

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

    Fixed in 5.4.0-1019.22
  41. Upgrade

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

    Fixed in 5.4.0-1051.55
  42. Upgrade

    Upgrade ubuntu/linux-gcp-5.11 to a version that resolves this vulnerability.

    Fixed in 5.11.0-1018.20~20.04.2
  43. Upgrade

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

    Fixed in 5.4.0-1051.54
  44. Upgrade

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

    Fixed in 5.4.0-1022.23
  45. Upgrade

    Upgrade ubuntu/linux-hwe-5.11 to a version that resolves this vulnerability.

    Fixed in 5.11.0-34.36~20.04.1
  46. Upgrade

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

    Fixed in 5.4.0-1045.47
  47. Upgrade

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

    Fixed in 5.10.0-1038.40
  48. Upgrade

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

    Fixed in 5.4.0-1053.57
  49. Upgrade

    Upgrade ubuntu/linux-oracle-5.11 to a version that resolves this vulnerability.

    Fixed in 5.11.0-1017.18~20.04.1
  50. Upgrade

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

    Fixed in 5.4.0-1042.46
  51. Upgrade

    Upgrade ubuntu/linux-riscv-5.11 to a version that resolves this vulnerability.

    Fixed in 5.11.0-1018.19~20.04.2
  52. Upgrade

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

    Fixed in 5.4.0-1069.73+fips2
  53. Upgrade

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

    Fixed in 5.4.0-1073.76+fips1
  54. Upgrade

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

    Fixed in 5.4.0-1032.37
  55. 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

Jun 14, 2021
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
Description
Data Sourced
via OSV·10:15 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·10:15 PM
RemedyDescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2021-34693?

CVE-2021-34693 has a medium severity rating due to the potential exposure of sensitive information.

2

How do I fix CVE-2021-34693?

To fix CVE-2021-34693, upgrade to the patched versions of the Linux kernel or the appropriate Debian packages specified in the vulnerability description.

3

Who is affected by CVE-2021-34693?

CVE-2021-34693 affects local users of Linux kernel versions up to 5.12.10 and specific Debian Linux versions.

4

What type of vulnerability is CVE-2021-34693?

CVE-2021-34693 is classified as a local information disclosure vulnerability due to uninitialized variables.

5

Can CVE-2021-34693 allow unauthorized access?

CVE-2021-34693 does not allow remote access but can provide local users access to sensitive kernel stack memory.

Company

Resources

Contact

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