CVE-2023-32254: Linux Kernel ksmbd Tree Connection Race Condition Remote Code Execution Vulnerability

Published Apr 28, 2023
·
Updated

A flaw was found in the Linux kernel's ksmbd, a high-performance in-kernel SMB server. The specific flaw exists within the processing of SMB2TREEDISCONNECT commands. The issue results from the lack of proper locking when performing operations on an object. An attacker can leverage this vulnerability to execute code in the context of the kernel.

Other sources

An improper locking issue leading to a race condition vulnerability was found in ksmbd, a high-performance in-kernel SMB server. Quoting ZDI security advisory [1]:

"This vulnerability allows remote attackers to execute arbitrary code on affected installations of Linux Kernel. Authentication is not required to exploit this vulnerability, but only systems with ksmbd enabled are vulnerable.

The specific flaw exists within the processing of SMB2TREEDISCONNECT commands. The issue results from the lack of proper locking when performing operations on an object. An attacker can leverage this vulnerability to execute code in the context of the kernel."

[1] https://www.zerodayinitiative.com/advisories/ZDI-CAN-20592/

— Red Hat

Affected Software

108 affected componentsFixes available
redhat/kernel<6.4
6.4
Linux Linux kernel<6.4
Linux Kernel
Linux Linux kernel>=5.15<5.15.145
Linux Linux kernel>=5.16<6.1.28
Linux Linux kernel>=6.2<6.2.15
Linux Linux kernel>=6.3<6.3.2
NetApp Hci Management Node
NetApp H300s
NetApp H410s
NetApp H500s
NetApp H700s
debian/linux
6.1.176-16.1.190-16.12.107-16.12.116-17.2.15-17.3.3-1
ubuntu/linux-hwe-edge*
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-gke-4.15*
ubuntu/linux-gke-5.4*
ubuntu/linux-gkeop-5.4*
ubuntu/linux-hwe*
ubuntu/linux-oem*
ubuntu/linux-oracle-5.0*
ubuntu/linux-oracle-5.3*
ubuntu/linux-aws-5.15<5.15.0-1057.63~20.04.1
5.15.0-1057.63~20.04.1
ubuntu/linux-azure-5.15<5.15.0-1060.69~20.04.1
5.15.0-1060.69~20.04.1
ubuntu/linux-gcp-5.15<5.15.0-1055.63~20.04.1
5.15.0-1055.63~20.04.1
ubuntu/linux-gkeop-5.15<5.15.0-1040.46~20.04.1
5.15.0-1040.46~20.04.1
ubuntu/linux-hwe-5.15<5.15.0-102.112~20.04.1
5.15.0-102.112~20.04.1
ubuntu/linux-ibm-5.15<5.15.0-1050.53~20.04.1
5.15.0-1050.53~20.04.1
ubuntu/linux-intel-iotg-5.15<5.15.0-1052.58~20.04.1
5.15.0-1052.58~20.04.1
ubuntu/linux-lowlatency-hwe-5.15<5.15.0-102.112~20.04.1
5.15.0-102.112~20.04.1
ubuntu/linux-nvidia-tegra-5.15<5.15.0-1025.25~20.04.1
5.15.0-1025.25~20.04.1
ubuntu/linux-oracle-5.15<5.15.0-1055.61~20.04.1
5.15.0-1055.61~20.04.1
ubuntu/linux-riscv-5.15<5.15.0-1053.57~20.04.1
5.15.0-1053.57~20.04.1
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-gke-5.15*
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<5.15.0-102.112
5.15.0-102.112
ubuntu/linux-allwinner-5.19*
ubuntu/linux-aws<5.15.0-1057.63
5.15.0-1057.63
ubuntu/linux-aws-5.19*
ubuntu/linux-azure<5.15.0-1060.69
5.15.0-1060.69
ubuntu/linux-azure-5.19*
ubuntu/linux-azure-fde<5.15.0-1060.69.1
5.15.0-1060.69.1
ubuntu/linux-azure-fde-5.19*
ubuntu/linux-gcp<5.15.0-1055.63
5.15.0-1055.63
ubuntu/linux-gcp-5.19*
ubuntu/linux-gke<5.15.0-1054.59
5.15.0-1054.59
ubuntu/linux-gkeop<5.15.0-1040.46
5.15.0-1040.46
ubuntu/linux-hwe-5.19*
ubuntu/linux-ibm<5.15.0-1050.53
5.15.0-1050.53
ubuntu/linux-intel-iotg<5.15.0-1052.58
5.15.0-1052.58
ubuntu/linux-kvm<5.15.0-1054.59
5.15.0-1054.59
ubuntu/linux-lowlatency<5.15.0-102.112
5.15.0-102.112
ubuntu/linux-lowlatency-hwe-5.19*
ubuntu/linux-nvidia<5.15.0-1048.48
5.15.0-1048.48
ubuntu/linux-nvidia-6.2<6.2.0-1010.10
6.2.0-1010.10
ubuntu/linux-nvidia-tegra<5.15.0-1025.25
5.15.0-1025.25
ubuntu/linux-nvidia-tegra-igx<5.15.0-1012.12
5.15.0-1012.12
ubuntu/linux-oem-5.17*
ubuntu/linux-oem-6.0*
ubuntu/linux-oem-6.1<6.1.0-1014.14
6.1.0-1014.14
ubuntu/linux-oracle<5.15.0-1055.61
5.15.0-1055.61
ubuntu/linux-raspi<5.15.0-1050.53
5.15.0-1050.53
ubuntu/linux-realtime*
ubuntu/linux-riscv*
ubuntu/linux-riscv-5.19*
ubuntu/linux-starfive-5.19*
ubuntu/linux-xilinx-zynqmp<5.15.0-1030.34
5.15.0-1030.34
ubuntu/linux-bluefield<5.15.0-1040.42
5.15.0-1040.42
ubuntu/linux-intel-iot-realtime<5.15.0-1050.52
5.15.0-1050.52
ubuntu/linux-realtime<5.15.0-1058.66
5.15.0-1058.66
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux-aws-fips<5.15.0-1057.63+fips1
5.15.0-1057.63+fips1
ubuntu/linux-azure-fips<5.15.0-1060.69+fips1
5.15.0-1060.69+fips1
ubuntu/linux-fips<5.15.0-102.112+fips1
5.15.0-102.112+fips1
ubuntu/linux-gcp-fips<5.15.0-1055.63+fips2
5.15.0-1055.63+fips2
ubuntu/linux-raspi-realtime*
ubuntu/linux-vmware*

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

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

    Fixed in 6.4
  2. 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
  3. Upgrade

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

    Fixed in 5.15.0-1057.63~20.04.1
  4. Upgrade

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

    Fixed in 5.15.0-1060.69~20.04.1
  5. Upgrade

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

    Fixed in 5.15.0-1055.63~20.04.1
  6. Upgrade

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

    Fixed in 5.15.0-1040.46~20.04.1
  7. Upgrade

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

    Fixed in 5.15.0-102.112~20.04.1
  8. Upgrade

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

    Fixed in 5.15.0-1050.53~20.04.1
  9. Upgrade

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

    Fixed in 5.15.0-1052.58~20.04.1
  10. Upgrade

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

    Fixed in 5.15.0-102.112~20.04.1
  11. Upgrade

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

    Fixed in 5.15.0-1025.25~20.04.1
  12. Upgrade

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

    Fixed in 5.15.0-1055.61~20.04.1
  13. Upgrade

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

    Fixed in 5.15.0-1053.57~20.04.1
  14. Upgrade

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

    Fixed in 5.15.0-102.112
  15. Upgrade

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

    Fixed in 5.15.0-1057.63
  16. Upgrade

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

    Fixed in 5.15.0-1060.69
  17. Upgrade

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

    Fixed in 5.15.0-1060.69.1
  18. Upgrade

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

    Fixed in 5.15.0-1055.63
  19. Upgrade

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

    Fixed in 5.15.0-1054.59
  20. Upgrade

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

    Fixed in 5.15.0-1040.46
  21. Upgrade

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

    Fixed in 5.15.0-1050.53
  22. Upgrade

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

    Fixed in 5.15.0-1052.58
  23. Upgrade

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

    Fixed in 5.15.0-1054.59
  24. Upgrade

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

    Fixed in 5.15.0-102.112
  25. Upgrade

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

    Fixed in 5.15.0-1048.48
  26. Upgrade

    Upgrade ubuntu/linux-nvidia-6.2 to a version that resolves this vulnerability.

    Fixed in 6.2.0-1010.10
  27. Upgrade

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

    Fixed in 5.15.0-1025.25
  28. Upgrade

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

    Fixed in 5.15.0-1012.12
  29. Upgrade

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

    Fixed in 6.1.0-1014.14
  30. Upgrade

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

    Fixed in 5.15.0-1055.61
  31. Upgrade

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

    Fixed in 5.15.0-1050.53
  32. Upgrade

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

    Fixed in 5.15.0-1030.34
  33. Upgrade

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

    Fixed in 5.15.0-1040.42
  34. Upgrade

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

    Fixed in 5.15.0-1050.52
  35. Upgrade

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

    Fixed in 5.15.0-1058.66
  36. Upgrade

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

    Fixed in 5.15.0-1057.63+fips1
  37. Upgrade

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

    Fixed in 5.15.0-1060.69+fips1
  38. Upgrade

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

    Fixed in 5.15.0-102.112+fips1
  39. Upgrade

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

    Fixed in 5.15.0-1055.63+fips2

Event History

May 17, 2023
Advisory Published
via ZDI·12:00 AM
Data Sourced
via ZDI·12:00 AM
DescriptionSeverityAffected Software
May 23, 2023
CVE Published
via OSV·12:00 AM
Data Sourced
via OSV·12:00 AM
DescriptionSeverityAffected Software
Event
via OSV·12:00 AM
Jul 10, 2023
CVE Published
via MITRE·03:11 PM
Data Sourced
via MITRE·03:11 PM
DescriptionSeverityWeakness

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2023-32254?

CVE-2023-32254 is classified as a high severity vulnerability due to its potential to allow unauthorized access via improperly locked operations.

2

How do I fix CVE-2023-32254?

To mitigate CVE-2023-32254, update to the latest kernel versions as recommended by your Linux distribution, specifically versions 6.4 or patched versions of earlier kernels.

3

Which systems are affected by CVE-2023-32254?

CVE-2023-32254 affects various versions of the Linux kernel, specifically those between 5.15.0 and 6.4.

4

What type of vulnerability is CVE-2023-32254?

CVE-2023-32254 is a locking flaw in the Linux kernel's ksmbd SMB server that can be exploited through the processing of SMB2_TREE_DISCONNECT commands.

5

Who discovered CVE-2023-32254?

CVE-2023-32254 was reported through security advisories and tracked by the Zero Day Initiative.

Company

Resources

Contact

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