CVE-2025-22040: ksmbd: fix session use-after-free in multichannel connection

Published Apr 16, 2025
·
Updated

In the Linux kernel, the following vulnerability has been resolved:

ksmbd: fix session use-after-free in multichannel connection

There is a race condition between session setup and ksmbdsessionsderegister. The session can be freed before the connection is added to channel list of session. This patch check reference count of session before freeing it.

Affected Software

168 affected componentsFixes available
Linux Linux kernel
Linux Linux kernel>=5.15<6.1.134
Linux Linux kernel>=6.2<6.6.87
Linux Linux kernel>=6.7<6.12.23
Linux Linux kernel>=6.13<6.13.11
Linux Linux kernel>=6.14<6.14.2
Debian Debian Linux=11.0
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-hwe-edge*
ubuntu/linux-oem*
ubuntu/linux-oracle-5.0*
ubuntu/linux-oracle-5.3*
ubuntu/linux-aws-5.11*
ubuntu/linux-aws-5.13*
ubuntu/linux-aws-5.15*
ubuntu/linux-aws-5.8*
ubuntu/linux-azure-5.11*
ubuntu/linux-azure-5.13*
ubuntu/linux-azure-5.15*
ubuntu/linux-azure-5.8*
ubuntu/linux-azure-fde*
ubuntu/linux-azure-fde-5.15*
ubuntu/linux-gcp-5.11*
ubuntu/linux-gcp-5.13*
ubuntu/linux-gcp-5.15*
ubuntu/linux-gcp-5.8*
ubuntu/linux-gke*
ubuntu/linux-gke-5.15*
ubuntu/linux-gkeop*
ubuntu/linux-gkeop-5.15*
ubuntu/linux-hwe-5.11*
ubuntu/linux-hwe-5.13*
ubuntu/linux-hwe-5.15*
ubuntu/linux-hwe-5.8*
ubuntu/linux-ibm-5.15*
ubuntu/linux-intel-5.13*
ubuntu/linux-intel-iotg-5.15*
ubuntu/linux-lowlatency-hwe-5.15*
ubuntu/linux-nvidia-tegra-5.15*
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-5.15*
ubuntu/linux-oracle-5.8*
ubuntu/linux-raspi2*
ubuntu/linux-riscv*
ubuntu/linux-riscv-5.11*
ubuntu/linux-riscv-5.15*
ubuntu/linux-riscv-5.8*
ubuntu/linux*
ubuntu/linux-allwinner-5.19*
ubuntu/linux-aws*
ubuntu/linux-aws-5.19*
ubuntu/linux-aws-6.2*
ubuntu/linux-aws-6.5*
ubuntu/linux-aws-6.8<6.8.0-1041.43~22.04.1
6.8.0-1041.43~22.04.1
ubuntu/linux-azure*
ubuntu/linux-azure-5.19*
ubuntu/linux-azure-6.2*
ubuntu/linux-azure-6.5*
ubuntu/linux-azure-6.8<6.8.0-1041.47~22.04.1
6.8.0-1041.47~22.04.1
ubuntu/linux-azure-fde*
ubuntu/linux-azure-fde-5.19*
ubuntu/linux-azure-fde-6.2*
ubuntu/linux-gcp*
ubuntu/linux-gcp-5.19*
ubuntu/linux-gcp-6.2*
ubuntu/linux-gcp-6.5*
ubuntu/linux-gcp-6.8<6.8.0-1042.45~22.04.1
6.8.0-1042.45~22.04.1
ubuntu/linux-gke*
ubuntu/linux-gkeop*
ubuntu/linux-hwe-5.19*
ubuntu/linux-hwe-6.2*
ubuntu/linux-hwe-6.5*
ubuntu/linux-hwe-6.8<6.8.0-86.87~22.04.1
6.8.0-86.87~22.04.1
ubuntu/linux-ibm*
ubuntu/linux-ibm-6.8<6.8.0-1039.39~22.04.1
6.8.0-1039.39~22.04.1
ubuntu/linux-intel-iot-realtime*
ubuntu/linux-intel-iotg*
ubuntu/linux-kvm*
ubuntu/linux-lowlatency*
ubuntu/linux-lowlatency-hwe-5.19*
ubuntu/linux-lowlatency-hwe-6.2*
ubuntu/linux-lowlatency-hwe-6.5*
ubuntu/linux-lowlatency-hwe-6.8<6.8.0-86.87.1~22.04.1
6.8.0-86.87.1~22.04.1
ubuntu/linux-nvidia*
ubuntu/linux-nvidia-6.2*
ubuntu/linux-nvidia-6.5*
ubuntu/linux-nvidia-6.8<6.8.0-1041.44~22.04.2
6.8.0-1041.44~22.04.2
ubuntu/linux-nvidia-tegra*
ubuntu/linux-nvidia-tegra-igx*
ubuntu/linux-oem-5.17*
ubuntu/linux-oem-6.0*
ubuntu/linux-oem-6.1*
ubuntu/linux-oem-6.5*
ubuntu/linux-oracle*
ubuntu/linux-oracle-6.5*
ubuntu/linux-oracle-6.8<6.8.0-1038.39~22.04.1
6.8.0-1038.39~22.04.1
ubuntu/linux-raspi*
ubuntu/linux-realtime*
ubuntu/linux-riscv*
ubuntu/linux-riscv-5.19*
ubuntu/linux-riscv-6.5*
ubuntu/linux-riscv-6.8<6.8.0-86.87~22.04.1
6.8.0-86.87~22.04.1
ubuntu/linux-starfive-5.19*
ubuntu/linux-starfive-6.2*
ubuntu/linux-starfive-6.5*
ubuntu/linux-xilinx-zynqmp*
ubuntu/linux-bluefield*
ubuntu/linux-intel-iot-realtime*
ubuntu/linux-realtime*
ubuntu/linux-realtime-6.8<6.8.1-1036.37~22.04.1
6.8.1-1036.37~22.04.1
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<6.8.0-86.87
6.8.0-86.87
ubuntu/linux-aws<6.8.0-1041.43
6.8.0-1041.43
ubuntu/linux-azure<6.8.0-1041.47
6.8.0-1041.47
ubuntu/linux-azure-6.11<6.11.0-1018.18~24.04.1
6.11.0-1018.18~24.04.1
ubuntu/linux-azure-nvidia<6.8.0-1029.32
6.8.0-1029.32
ubuntu/linux-gcp<6.8.0-1042.45
6.8.0-1042.45
ubuntu/linux-gcp-6.11<6.11.0-1016.16~24.04.1
6.11.0-1016.16~24.04.1
ubuntu/linux-gke<6.8.0-1038.43
6.8.0-1038.43
ubuntu/linux-gkeop<6.8.0-1025.28
6.8.0-1025.28
ubuntu/linux-hwe-6.11<6.11.0-28.28~24.04.1
6.11.0-28.28~24.04.1
ubuntu/linux-ibm<6.8.0-1039.39
6.8.0-1039.39
ubuntu/linux-intel*
ubuntu/linux-lowlatency<6.8.0-86.87.1
6.8.0-86.87.1
ubuntu/linux-lowlatency-hwe-6.11<6.11.0-1015.16~24.04.2
6.11.0-1015.16~24.04.2
ubuntu/linux-nvidia<6.8.0-1041.44
6.8.0-1041.44
ubuntu/linux-nvidia-6.11<6.11.0-1012.12
6.11.0-1012.12
ubuntu/linux-nvidia-lowlatency<6.8.0-1041.44.1
6.8.0-1041.44.1
ubuntu/linux-nvidia-tegra<6.8.0-1012.12
6.8.0-1012.12
ubuntu/linux-oem-6.11<6.11.0-1024.24
6.11.0-1024.24
ubuntu/linux-oem-6.8*
ubuntu/linux-oracle<6.8.0-1038.39
6.8.0-1038.39
ubuntu/linux-raspi<6.8.0-1041.45
6.8.0-1041.45
ubuntu/linux-raspi-realtime*
ubuntu/linux-realtime*
ubuntu/linux-riscv*
ubuntu/linux-xilinx<6.8.0-1018.19
6.8.0-1018.19
ubuntu/linux-bluefield<6.8.0-1012.16
6.8.0-1012.16
ubuntu/linux-raspi-realtime<6.8.0-2032.33
6.8.0-2032.33
ubuntu/linux-realtime<6.8.1-1036.37
6.8.1-1036.37
ubuntu/linux-aws-fips<6.8.0-1041.43+fips1
6.8.0-1041.43+fips1
ubuntu/linux-azure-fips<6.8.0-1044.50+fips1
6.8.0-1044.50+fips1
ubuntu/linux-fips<6.8.0-86.87+fips1
6.8.0-86.87+fips1
ubuntu/linux-gcp-fips<6.8.0-1042.45+fips1
6.8.0-1042.45+fips1
ubuntu/linux-azure-fde*
debian/linux
6.1.176-16.1.190-16.12.107-16.12.115-27.2.12-17.2.15-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade ubuntu/linux-aws-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1041.43~22.04.1
  2. Upgrade

    Upgrade ubuntu/linux-azure-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1041.47~22.04.1
  3. Upgrade

    Upgrade ubuntu/linux-gcp-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1042.45~22.04.1
  4. Upgrade

    Upgrade ubuntu/linux-hwe-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-86.87~22.04.1
  5. Upgrade

    Upgrade ubuntu/linux-ibm-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1039.39~22.04.1
  6. Upgrade

    Upgrade ubuntu/linux-lowlatency-hwe-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-86.87.1~22.04.1
  7. Upgrade

    Upgrade ubuntu/linux-nvidia-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1041.44~22.04.2
  8. Upgrade

    Upgrade ubuntu/linux-oracle-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1038.39~22.04.1
  9. Upgrade

    Upgrade ubuntu/linux-riscv-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-86.87~22.04.1
  10. Upgrade

    Upgrade ubuntu/linux-realtime-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.1-1036.37~22.04.1
  11. Upgrade

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

    Fixed in 6.8.0-86.87
  12. Upgrade

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

    Fixed in 6.8.0-1041.43
  13. Upgrade

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

    Fixed in 6.8.0-1041.47
  14. Upgrade

    Upgrade ubuntu/linux-azure-6.11 to a version that resolves this vulnerability.

    Fixed in 6.11.0-1018.18~24.04.1
  15. Upgrade

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

    Fixed in 6.8.0-1029.32
  16. Upgrade

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

    Fixed in 6.8.0-1042.45
  17. Upgrade

    Upgrade ubuntu/linux-gcp-6.11 to a version that resolves this vulnerability.

    Fixed in 6.11.0-1016.16~24.04.1
  18. Upgrade

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

    Fixed in 6.8.0-1038.43
  19. Upgrade

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

    Fixed in 6.8.0-1025.28
  20. Upgrade

    Upgrade ubuntu/linux-hwe-6.11 to a version that resolves this vulnerability.

    Fixed in 6.11.0-28.28~24.04.1
  21. Upgrade

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

    Fixed in 6.8.0-1039.39
  22. Upgrade

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

    Fixed in 6.8.0-86.87.1
  23. Upgrade

    Upgrade ubuntu/linux-lowlatency-hwe-6.11 to a version that resolves this vulnerability.

    Fixed in 6.11.0-1015.16~24.04.2
  24. Upgrade

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

    Fixed in 6.8.0-1041.44
  25. Upgrade

    Upgrade ubuntu/linux-nvidia-6.11 to a version that resolves this vulnerability.

    Fixed in 6.11.0-1012.12
  26. Upgrade

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

    Fixed in 6.8.0-1041.44.1
  27. Upgrade

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

    Fixed in 6.8.0-1012.12
  28. Upgrade

    Upgrade ubuntu/linux-oem-6.11 to a version that resolves this vulnerability.

    Fixed in 6.11.0-1024.24
  29. Upgrade

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

    Fixed in 6.8.0-1038.39
  30. Upgrade

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

    Fixed in 6.8.0-1041.45
  31. Upgrade

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

    Fixed in 6.8.0-1018.19
  32. Upgrade

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

    Fixed in 6.8.0-1012.16
  33. Upgrade

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

    Fixed in 6.8.0-2032.33
  34. Upgrade

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

    Fixed in 6.8.1-1036.37
  35. Upgrade

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

    Fixed in 6.8.0-1041.43+fips1
  36. Upgrade

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

    Fixed in 6.8.0-1044.50+fips1
  37. Upgrade

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

    Fixed in 6.8.0-86.87+fips1
  38. Upgrade

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

    Fixed in 6.8.0-1042.45+fips1
  39. 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 6.12.115-2Fixed in 7.2.12-1Fixed in 7.2.15-1

Event History

Apr 16, 2025
CVE Published
via MITRE·02:11 PM
Data Sourced
via MITRE·02:11 PM
DescriptionSeverity
Data Sourced
via OSV·03:15 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·03:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
Jul 11, 2025
Data Sourced
via Microsoft·07:00 AM
DescriptionSeverityWeakness

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-2025-22040?

CVE-2025-22040 is classified as a medium severity vulnerability due to the potential for a race condition affecting session management.

2

How do I fix CVE-2025-22040?

To fix CVE-2025-22040, you should update your Linux kernel to the latest patched version that addresses this vulnerability.

3

What impact does CVE-2025-22040 have on system security?

CVE-2025-22040 can lead to session instability or unauthorized access if exploited, affecting the security of the affected system.

4

Which versions of the Linux kernel are affected by CVE-2025-22040?

CVE-2025-22040 affects specific versions of the Linux kernel, particularly those prior to the fix being applied as per the updates.

5

Is CVE-2025-22040 exploitable remotely?

CVE-2025-22040 could potentially be exploited remotely, depending on the specific configurations and use of ksmbd in the Linux environment.

Company

Resources

Contact

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