CVE-2025-37899: ksmbd: fix use-after-free in session logoff

Published May 20, 2025
·
Updated

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

ksmbd: fix use-after-free in session logoff

The sess->user object can currently be in use by another thread, for example if another connection has sent a session setup request to bind to the session being free'd. The handler for that connection could be in the smb2sesssetup function which makes use of sess->user.

Affected Software

176 affected componentsFixes available
Linux Linux kernel
Linux Linux kernel>=5.15<6.12.28
Linux Linux kernel>=6.13<6.14.6
Linux Linux kernel=6.15-rc1
Linux Linux kernel=6.15-rc2
Linux Linux kernel=6.15-rc3
Linux Linux kernel=6.15-rc4
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<6.8.0-1047.50~22.04.1
6.8.0-1047.50~22.04.1
ubuntu/linux-azure*
ubuntu/linux-azure-5.19*
ubuntu/linux-azure-6.2*
ubuntu/linux-azure-6.5*
ubuntu/linux-azure-6.8<6.8.0-1051.57~22.04.1
6.8.0-1051.57~22.04.1
ubuntu/linux-azure-fde*
ubuntu/linux-azure-fde-5.19*
ubuntu/linux-azure-fde-6.2*
ubuntu/linux-azure-fde-6.8<6.8.0-1058.65~22.04.1
6.8.0-1058.65~22.04.1
ubuntu/linux-gcp*
ubuntu/linux-gcp-5.19*
ubuntu/linux-gcp-6.2*
ubuntu/linux-gcp-6.5*
ubuntu/linux-gcp-6.8<6.8.0-1048.51~22.04.1
6.8.0-1048.51~22.04.1
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<6.8.0-101.101~22.04.1
6.8.0-101.101~22.04.1
ubuntu/linux-ibm*
ubuntu/linux-ibm-6.8<6.8.0-1045.45~22.04.1
6.8.0-1045.45~22.04.1
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<6.8.0-101.101.1~22.04.1
6.8.0-101.101.1~22.04.1
ubuntu/linux-nvidia*
ubuntu/linux-nvidia-6.2*
ubuntu/linux-nvidia-6.5*
ubuntu/linux-nvidia-6.8<6.8.0-1047.50~22.04.1
6.8.0-1047.50~22.04.1
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<6.8.0-1044.45~22.04.1
6.8.0-1044.45~22.04.1
ubuntu/linux-raspi*
ubuntu/linux-realtime*
ubuntu/linux-riscv*
ubuntu/linux-riscv-5.19*
ubuntu/linux-riscv-6.5*
ubuntu/linux-riscv-6.8<6.8.0-101.101~22.04.1
6.8.0-101.101~22.04.1
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<6.8.1-1042.43~22.04.1
6.8.1-1042.43~22.04.1
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<6.8.0-101.101
6.8.0-101.101
ubuntu/linux-aws<6.8.0-1047.50
6.8.0-1047.50
ubuntu/linux-aws-6.14<6.14.0-1009.9~24.04.1
6.14.0-1009.9~24.04.1
ubuntu/linux-azure<6.8.0-1051.57
6.8.0-1051.57
ubuntu/linux-azure-6.11*
ubuntu/linux-azure-fde<6.8.0-1058.65
6.8.0-1058.65
ubuntu/linux-azure-nvidia<6.8.0-1039.42
6.8.0-1039.42
ubuntu/linux-gcp<6.8.0-1048.51
6.8.0-1048.51
ubuntu/linux-gcp-6.11*
ubuntu/linux-gcp-6.14<6.14.0-1011.11~24.04.1
6.14.0-1011.11~24.04.1
ubuntu/linux-gke<6.8.0-1044.49
6.8.0-1044.49
ubuntu/linux-gkeop<6.8.0-1031.34
6.8.0-1031.34
ubuntu/linux-hwe-6.11*
ubuntu/linux-ibm<6.8.0-1045.45
6.8.0-1045.45
ubuntu/linux-intel*
ubuntu/linux-lowlatency<6.8.0-101.101.1
6.8.0-101.101.1
ubuntu/linux-lowlatency-hwe-6.11*
ubuntu/linux-nvidia<6.8.0-1047.50
6.8.0-1047.50
ubuntu/linux-nvidia-6.11*
ubuntu/linux-nvidia-lowlatency<6.8.0-1047.50.1
6.8.0-1047.50.1
ubuntu/linux-nvidia-tegra<6.8.0-1020.20
6.8.0-1020.20
ubuntu/linux-oem-6.11*
ubuntu/linux-oem-6.14<6.14.0-1007.7
6.14.0-1007.7
ubuntu/linux-oem-6.8*
ubuntu/linux-oracle<6.8.0-1044.45
6.8.0-1044.45
ubuntu/linux-oracle-6.14<6.14.0-1009.9~24.04.1
6.14.0-1009.9~24.04.1
ubuntu/linux-raspi<6.8.0-1048.52
6.8.0-1048.52
ubuntu/linux-raspi-realtime*
ubuntu/linux-realtime*
ubuntu/linux-riscv*
ubuntu/linux-riscv-6.14<6.14.0-24.24.1~24.04.1
6.14.0-24.24.1~24.04.1
ubuntu/linux-xilinx<6.8.0-1024.25
6.8.0-1024.25
ubuntu/linux-bluefield<6.8.0-1017.21
6.8.0-1017.21
ubuntu/linux-raspi-realtime<6.8.0-2038.39
6.8.0-2038.39
ubuntu/linux-realtime<6.8.1-1042.43
6.8.1-1042.43
ubuntu/linux-realtime-6.14<6.14.0-1010.10~24.04.1
6.14.0-1010.10~24.04.1
ubuntu/linux-aws-fips<6.8.0-1047.50+fips1
6.8.0-1047.50+fips1
ubuntu/linux-azure-fips<6.8.0-1047.53+fips1
6.8.0-1047.53+fips1
ubuntu/linux-fips<6.8.0-101.101+fips1
6.8.0-101.101+fips1
ubuntu/linux-gcp-fips<6.8.0-1048.51+fips1
6.8.0-1048.51+fips1
ubuntu/linux-azure-fde*
ubuntu/linux-vmware*

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 6.8.0-1047.50~22.04.1
  2. Upgrade

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

    Fixed in 6.8.0-1051.57~22.04.1
  3. Upgrade

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

    Fixed in 6.8.0-1058.65~22.04.1
  4. Upgrade

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

    Fixed in 6.8.0-1048.51~22.04.1
  5. Upgrade

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

    Fixed in 6.8.0-101.101~22.04.1
  6. Upgrade

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

    Fixed in 6.8.0-1045.45~22.04.1
  7. Upgrade

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

    Fixed in 6.8.0-101.101.1~22.04.1
  8. Upgrade

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

    Fixed in 6.8.0-1047.50~22.04.1
  9. Upgrade

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

    Fixed in 6.8.0-1044.45~22.04.1
  10. Upgrade

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

    Fixed in 6.8.0-101.101~22.04.1
  11. Upgrade

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

    Fixed in 6.8.1-1042.43~22.04.1
  12. Upgrade

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

    Fixed in 6.8.0-101.101
  13. Upgrade

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

    Fixed in 6.8.0-1047.50
  14. Upgrade

    Upgrade ubuntu/linux-aws-6.14 to a version that resolves this vulnerability.

    Fixed in 6.14.0-1009.9~24.04.1
  15. Upgrade

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

    Fixed in 6.8.0-1051.57
  16. Upgrade

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

    Fixed in 6.8.0-1058.65
  17. Upgrade

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

    Fixed in 6.8.0-1039.42
  18. Upgrade

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

    Fixed in 6.8.0-1048.51
  19. Upgrade

    Upgrade ubuntu/linux-gcp-6.14 to a version that resolves this vulnerability.

    Fixed in 6.14.0-1011.11~24.04.1
  20. Upgrade

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

    Fixed in 6.8.0-1044.49
  21. Upgrade

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

    Fixed in 6.8.0-1031.34
  22. Upgrade

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

    Fixed in 6.8.0-1045.45
  23. Upgrade

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

    Fixed in 6.8.0-101.101.1
  24. Upgrade

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

    Fixed in 6.8.0-1047.50
  25. Upgrade

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

    Fixed in 6.8.0-1047.50.1
  26. Upgrade

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

    Fixed in 6.8.0-1020.20
  27. Upgrade

    Upgrade ubuntu/linux-oem-6.14 to a version that resolves this vulnerability.

    Fixed in 6.14.0-1007.7
  28. Upgrade

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

    Fixed in 6.8.0-1044.45
  29. Upgrade

    Upgrade ubuntu/linux-oracle-6.14 to a version that resolves this vulnerability.

    Fixed in 6.14.0-1009.9~24.04.1
  30. Upgrade

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

    Fixed in 6.8.0-1048.52
  31. Upgrade

    Upgrade ubuntu/linux-riscv-6.14 to a version that resolves this vulnerability.

    Fixed in 6.14.0-24.24.1~24.04.1
  32. Upgrade

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

    Fixed in 6.8.0-1024.25
  33. Upgrade

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

    Fixed in 6.8.0-1017.21
  34. Upgrade

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

    Fixed in 6.8.0-2038.39
  35. Upgrade

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

    Fixed in 6.8.1-1042.43
  36. Upgrade

    Upgrade ubuntu/linux-realtime-6.14 to a version that resolves this vulnerability.

    Fixed in 6.14.0-1010.10~24.04.1
  37. Upgrade

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

    Fixed in 6.8.0-1047.50+fips1
  38. Upgrade

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

    Fixed in 6.8.0-1047.53+fips1
  39. Upgrade

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

    Fixed in 6.8.0-101.101+fips1
  40. Upgrade

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

    Fixed in 6.8.0-1048.51+fips1

Event History

May 20, 2025
CVE Published
via MITRE·03:21 PM
Data Sourced
via MITRE·03:21 PM
DescriptionSeverity
Data Sourced
via OSV·04:15 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·04:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
May 22, 2025
Exploit Published
via GitHub·10:36 AM
Sep 4, 2025
Data Sourced
via Microsoft·01:01 AM
DescriptionSeverityWeakness

Frequently Asked Questions

1

What is the severity of CVE-2025-37899?

CVE-2025-37899 is classified as a medium severity vulnerability in the Linux kernel.

2

How do I fix CVE-2025-37899?

To fix CVE-2025-37899, update to the latest version of the Linux kernel that includes the patch for the use-after-free vulnerability.

3

What systems are affected by CVE-2025-37899?

CVE-2025-37899 affects the Linux kernel, specifically implementations using the ksmbd component.

4

What is the impact of CVE-2025-37899?

The impact of CVE-2025-37899 includes potential exploitation leading to improper memory management and possible system instability.

5

When was CVE-2025-37899 published?

CVE-2025-37899 was published as part of ongoing security vigilance for the Linux kernel, though the exact publication date may vary.

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