CVE-2023-1076: Medium severity Linux Linux kernel vulnerability

Published Feb 26, 2023
·
Updated

A flaw found in the Linux Kernel. The tun/tap sockets have their socket UID hardcoded to 0 due to a type confusion in their initialization function. While it will be often correct, as tuntap devices require CAPNETADMIN, it may not always be the case, e.g., a non-root user only having that capability. This would make tun/tap sockets being incorrectly treated in filtering/routing decisions, possibly bypassing network filters.

References: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=66b2c338adce580dfce2199591e65e2bab889cff https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=a096ccca6e503a5c575717ff8a36ace27510ab0a

Other sources

A flaw was found in the Linux Kernel. The tun/tap sockets have their socket UID hardcoded to 0 due to a type confusion in their initialization function. While it will be often correct, as tuntap devices require CAPNETADMIN, it may not always be the case, e.g., a non-root user only having that capability. This would make tun/tap sockets being incorrectly treated in filtering/routing decisions, possibly bypassing network filters.

— Launchpad

Affected Software

131 affected componentsFixes available
Linux Linux kernel
debian/linux
5.10.223-15.10.234-16.1.129-16.1.135-16.12.25-16.12.27-1
redhat/kernel<6.1.16
6.1.16
ubuntu/linux-azure*
ubuntu/linux-aws-hwe*
ubuntu/linux-azure*
ubuntu/linux-gcp*
ubuntu/linux-hwe*
ubuntu/linux-hwe-edge*
ubuntu/linux-oracle*
ubuntu/linux*
ubuntu/linux-aws*
ubuntu/linux-aws-5.0*
ubuntu/linux-aws-5.3*
ubuntu/linux-aws-5.4<5.4.0-1104.112~18.04.1
5.4.0-1104.112~18.04.1
ubuntu/linux-azure*
ubuntu/linux-azure-4.15*
ubuntu/linux-azure-5.3*
ubuntu/linux-azure-5.4<5.4.0-1110.116~18.04.1
5.4.0-1110.116~18.04.1
ubuntu/linux-azure-edge*
ubuntu/linux-gcp*
ubuntu/linux-gcp-4.15*
ubuntu/linux-gcp-5.3*
ubuntu/linux-gcp-5.4<5.4.0-1107.116~18.04.1
5.4.0-1107.116~18.04.1
ubuntu/linux-gke-4.15*
ubuntu/linux-gke-5.4*
ubuntu/linux-gkeop-5.4*
ubuntu/linux-hwe*
ubuntu/linux-hwe-5.4<5.4.0-152.169~18.04.1
5.4.0-152.169~18.04.1
ubuntu/linux-hwe-edge*
ubuntu/linux-ibm-5.4<5.4.0-1051.56~18.04.1
5.4.0-1051.56~18.04.1
ubuntu/linux-kvm*
ubuntu/linux-oem*
ubuntu/linux-oracle*
ubuntu/linux-oracle-5.0*
ubuntu/linux-oracle-5.3*
ubuntu/linux-oracle-5.4<5.4.0-1103.112~18.04.1
5.4.0-1103.112~18.04.1
ubuntu/linux-raspi-5.4<5.4.0-1088.99~18.04.1
5.4.0-1088.99~18.04.1
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux<5.4.0-152.169
5.4.0-152.169
ubuntu/linux-aws<5.4.0-1104.112
5.4.0-1104.112
ubuntu/linux-aws-5.15<5.15.0-1038.43~20.04.1
5.15.0-1038.43~20.04.1
ubuntu/linux-azure<5.4.0-1110.116
5.4.0-1110.116
ubuntu/linux-azure-5.15<5.15.0-1040.47~20.04.1
5.15.0-1040.47~20.04.1
ubuntu/linux-bluefield<5.4.0-1065.71
5.4.0-1065.71
ubuntu/linux-gcp<5.4.0-1107.116
5.4.0-1107.116
ubuntu/linux-gcp-5.15<5.15.0-1036.44~20.04.1
5.15.0-1036.44~20.04.1
ubuntu/linux-gke<5.4.0-1102.109
5.4.0-1102.109
ubuntu/linux-gke-5.15<5.15.0-1036.41~20.04.1
5.15.0-1036.41~20.04.1
ubuntu/linux-gkeop<5.4.0-1071.75
5.4.0-1071.75
ubuntu/linux-gkeop-5.15<5.15.0-1022.27~20.04.1
5.15.0-1022.27~20.04.1
ubuntu/linux-hwe-5.15<5.15.0-75.82~20.04.1
5.15.0-75.82~20.04.1
ubuntu/linux-ibm<5.4.0-1051.56
5.4.0-1051.56
ubuntu/linux-intel-iotg-5.15<5.15.0-1033.38~20.04.1
5.15.0-1033.38~20.04.1
ubuntu/linux-iot<5.4.0-1017.18
5.4.0-1017.18
ubuntu/linux-kvm<5.4.0-1093.99
5.4.0-1093.99
ubuntu/linux-lowlatency-hwe-5.15<5.15.0-75.82~20.04.1
5.15.0-75.82~20.04.1
ubuntu/linux-nvidia-tegra-5.15<5.15.0-1015.15~20.04.1
5.15.0-1015.15~20.04.1
ubuntu/linux-oracle<5.4.0-1103.112
5.4.0-1103.112
ubuntu/linux-oracle-5.15<5.15.0-1037.43~20.04.1
5.15.0-1037.43~20.04.1
ubuntu/linux-raspi<5.4.0-1088.99
5.4.0-1088.99
ubuntu/linux-riscv-5.15<5.15.0-1035.39~20.04.1
5.15.0-1035.39~20.04.1
ubuntu/linux-xilinx-zynqmp<5.4.0-1024.28
5.4.0-1024.28
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-azure-fde-5.15<5.15.0-1114.123~20.04.1
5.15.0-1114.123~20.04.1
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<5.4.0-1104.112+fips1
5.4.0-1104.112+fips1
ubuntu/linux-azure-fips<5.4.0-1110.116+fips1
5.4.0-1110.116+fips1
ubuntu/linux-fips<5.4.0-1079.88
5.4.0-1079.88
ubuntu/linux-gcp-fips<5.4.0-1107.116+fips1
5.4.0-1107.116+fips1
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux<5.15.0-75.82
5.15.0-75.82
ubuntu/linux-aws<5.15.0-1038.43
5.15.0-1038.43
ubuntu/linux-azure<5.15.0-1040.47
5.15.0-1040.47
ubuntu/linux-azure-5.19*
ubuntu/linux-azure-fde<5.15.0-1041.48.1
5.15.0-1041.48.1
ubuntu/linux-azure-fde-5.19*
ubuntu/linux-gcp<5.15.0-1036.44
5.15.0-1036.44
ubuntu/linux-gke<5.15.0-1036.41
5.15.0-1036.41
ubuntu/linux-gkeop<5.15.0-1022.27
5.15.0-1022.27
ubuntu/linux-hwe-5.19<5.19.0-45.46~22.04.1
5.19.0-45.46~22.04.1
ubuntu/linux-ibm<5.15.0-1032.35
5.15.0-1032.35
ubuntu/linux-intel-iotg<5.15.0-1033.38
5.15.0-1033.38
ubuntu/linux-kvm<5.15.0-1035.40
5.15.0-1035.40
ubuntu/linux-lowlatency<5.15.0-75.82
5.15.0-75.82
ubuntu/linux-nvidia<5.15.0-1027.27
5.15.0-1027.27
ubuntu/linux-nvidia-tegra<5.15.0-1015.15
5.15.0-1015.15
ubuntu/linux-oem-5.17*
ubuntu/linux-oem-6.0<6.0.0-1021.21
6.0.0-1021.21
ubuntu/linux-oem-6.1<6.1.0-1009.9
6.1.0-1009.9
ubuntu/linux-oracle<5.15.0-1037.43
5.15.0-1037.43
ubuntu/linux-raspi<5.15.0-1032.35
5.15.0-1032.35
ubuntu/linux-realtime*
ubuntu/linux-riscv*
ubuntu/linux-bluefield<5.15.0-1019.21
5.15.0-1019.21
ubuntu/linux-intel-iot-realtime<5.15.0-1033.35
5.15.0-1033.35
ubuntu/linux-realtime<5.15.0-1040.45
5.15.0-1040.45
ubuntu/linux-fips*
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 redhat/kernel to a version that resolves this vulnerability.

    Fixed in 6.1.16
  3. Upgrade

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

    Fixed in 5.4.0-1104.112~18.04.1
  4. Upgrade

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

    Fixed in 5.4.0-1110.116~18.04.1
  5. Upgrade

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

    Fixed in 5.4.0-1107.116~18.04.1
  6. Upgrade

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

    Fixed in 5.4.0-152.169~18.04.1
  7. Upgrade

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

    Fixed in 5.4.0-1051.56~18.04.1
  8. Upgrade

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

    Fixed in 5.4.0-1103.112~18.04.1
  9. Upgrade

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

    Fixed in 5.4.0-1088.99~18.04.1
  10. Upgrade

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

    Fixed in 5.4.0-152.169
  11. Upgrade

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

    Fixed in 5.4.0-1104.112
  12. Upgrade

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

    Fixed in 5.15.0-1038.43~20.04.1
  13. Upgrade

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

    Fixed in 5.4.0-1110.116
  14. Upgrade

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

    Fixed in 5.15.0-1040.47~20.04.1
  15. Upgrade

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

    Fixed in 5.4.0-1065.71
  16. Upgrade

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

    Fixed in 5.4.0-1107.116
  17. Upgrade

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

    Fixed in 5.15.0-1036.44~20.04.1
  18. Upgrade

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

    Fixed in 5.4.0-1102.109
  19. Upgrade

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

    Fixed in 5.15.0-1036.41~20.04.1
  20. Upgrade

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

    Fixed in 5.4.0-1071.75
  21. Upgrade

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

    Fixed in 5.15.0-1022.27~20.04.1
  22. Upgrade

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

    Fixed in 5.15.0-75.82~20.04.1
  23. Upgrade

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

    Fixed in 5.4.0-1051.56
  24. Upgrade

    Upgrade ubuntu/linux-intel-iotg-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1033.38~20.04.1
  25. Upgrade

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

    Fixed in 5.4.0-1017.18
  26. Upgrade

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

    Fixed in 5.4.0-1093.99
  27. Upgrade

    Upgrade ubuntu/linux-lowlatency-hwe-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-75.82~20.04.1
  28. Upgrade

    Upgrade ubuntu/linux-nvidia-tegra-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1015.15~20.04.1
  29. Upgrade

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

    Fixed in 5.4.0-1103.112
  30. Upgrade

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

    Fixed in 5.15.0-1037.43~20.04.1
  31. Upgrade

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

    Fixed in 5.4.0-1088.99
  32. Upgrade

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

    Fixed in 5.15.0-1035.39~20.04.1
  33. Upgrade

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

    Fixed in 5.4.0-1024.28
  34. 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
  35. Upgrade

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

    Fixed in 5.4.0-1104.112+fips1
  36. Upgrade

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

    Fixed in 5.4.0-1110.116+fips1
  37. Upgrade

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

    Fixed in 5.4.0-1079.88
  38. Upgrade

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

    Fixed in 5.4.0-1107.116+fips1
  39. Upgrade

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

    Fixed in 5.15.0-75.82
  40. Upgrade

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

    Fixed in 5.15.0-1038.43
  41. Upgrade

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

    Fixed in 5.15.0-1040.47
  42. Upgrade

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

    Fixed in 5.15.0-1041.48.1
  43. Upgrade

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

    Fixed in 5.15.0-1036.44
  44. Upgrade

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

    Fixed in 5.15.0-1036.41
  45. Upgrade

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

    Fixed in 5.15.0-1022.27
  46. Upgrade

    Upgrade ubuntu/linux-hwe-5.19 to a version that resolves this vulnerability.

    Fixed in 5.19.0-45.46~22.04.1
  47. Upgrade

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

    Fixed in 5.15.0-1032.35
  48. Upgrade

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

    Fixed in 5.15.0-1033.38
  49. Upgrade

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

    Fixed in 5.15.0-1035.40
  50. Upgrade

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

    Fixed in 5.15.0-75.82
  51. Upgrade

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

    Fixed in 5.15.0-1027.27
  52. Upgrade

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

    Fixed in 5.15.0-1015.15
  53. Upgrade

    Upgrade ubuntu/linux-oem-6.0 to a version that resolves this vulnerability.

    Fixed in 6.0.0-1021.21
  54. Upgrade

    Upgrade ubuntu/linux-oem-6.1 to a version that resolves this vulnerability.

    Fixed in 6.1.0-1009.9
  55. Upgrade

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

    Fixed in 5.15.0-1037.43
  56. Upgrade

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

    Fixed in 5.15.0-1032.35
  57. Upgrade

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

    Fixed in 5.15.0-1019.21
  58. Upgrade

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

    Fixed in 5.15.0-1033.35
  59. Upgrade

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

    Fixed in 5.15.0-1040.45

Event History

Feb 26, 2023
Data Sourced
via Red Hat·05:20 PM
DescriptionSeverityAffected Software
Mar 27, 2023
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
DescriptionWeakness
Data Sourced
via OSV·09:15 PM
DescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2023-1076?

CVE-2023-1076 has a high severity rating due to a vulnerability in the Linux Kernel affecting tun/tap sockets.

2

How do I fix CVE-2023-1076?

To fix CVE-2023-1076, upgrade to kernel version 6.1.16 or apply the relevant patches available for affected distributions.

3

Which versions of Linux Kernel are affected by CVE-2023-1076?

CVE-2023-1076 affects multiple versions including pre-6.1.16 and specific versions in the 5.10 and 6.x series without the patch.

4

Under what conditions does CVE-2023-1076 pose a risk?

CVE-2023-1076 poses a risk particularly when non-root users gain unintended access through tun/tap socket misuse.

5

What is the root cause of CVE-2023-1076?

The root cause of CVE-2023-1076 is a type confusion in the initialization function for tun/tap sockets leading to hard-coded UID issues.

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