CVE-2026-90152: smb/server: fix session leak in ksmbd_session_register()

Published Sep 17, 2026
·
Updated

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

smb/server: fix session leak in ksmbdsessionregister()

See the procedure below:

smb2sesssetup ksmbdsmb2sessioncreate sessioncreate atomicset(&sess->refcnt, 2) hashadd(sessionstable, &sess->hlist, sess->id) ksmbdsessionregister xastore(&conn->sessions, sess->id, sess) // fail ksmbdusersessionput atomicdec(&sess->refcnt) // refcnt is 1, session is not freed

Remove the session from sessionstable and drop its table reference if xastore() fails.

Affected Software

208 affected componentsFixes available
Linux Kernel
debian/linux*
debian/linux<6.12.111-1
6.12.111-1
debian/linux<7.2.6-1
7.2.6-1
debian/linux-6.12<6.12.111-1~deb12u1
6.12.111-1~deb12u1
linux/kernel<6.1.191
6.1.191
linux/kernel>=6.2.0<6.6.160
6.6.160
linux/kernel>=6.4.0<6.12.110
6.12.110
linux/kernel>=6.7.0<6.18.52
6.18.52
linux/kernel>=6.13.0<7.2.6
7.2.6
debian/linux<=6.1.176-1, <=6.1.190-1, <=6.12.107-1
6.12.115-27.2.12-17.2.15-1
debian/linux-6.12
6.12.113-1~deb12u1
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*
ubuntu/linux-azure*
ubuntu/linux-azure-5.19*
ubuntu/linux-azure-6.2*
ubuntu/linux-azure-6.5*
ubuntu/linux-azure-6.8*
ubuntu/linux-azure-fde*
ubuntu/linux-azure-fde-5.19*
ubuntu/linux-azure-fde-6.2*
ubuntu/linux-azure-fde-6.8*
ubuntu/linux-gcp*
ubuntu/linux-gcp-5.19*
ubuntu/linux-gcp-6.2*
ubuntu/linux-gcp-6.5*
ubuntu/linux-gcp-6.8*
ubuntu/linux-gke*
ubuntu/linux-gkeop*
ubuntu/linux-hwe-5.19*
ubuntu/linux-hwe-6.2*
ubuntu/linux-hwe-6.5*
ubuntu/linux-ibm*
ubuntu/linux-ibm-6.8*
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*
ubuntu/linux-nvidia*
ubuntu/linux-nvidia-6.2*
ubuntu/linux-nvidia-6.5*
ubuntu/linux-nvidia-6.8*
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*
ubuntu/linux-raspi*
ubuntu/linux-realtime*
ubuntu/linux-riscv*
ubuntu/linux-riscv-5.19*
ubuntu/linux-riscv-6.5*
ubuntu/linux-riscv-6.8*
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*
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux*
ubuntu/linux-aws*
ubuntu/linux-aws-6.14*
ubuntu/linux-aws-6.17*
ubuntu/linux-aws-7.0*
ubuntu/linux-azure*
ubuntu/linux-azure-6.11*
ubuntu/linux-azure-6.14*
ubuntu/linux-azure-6.17*
ubuntu/linux-azure-7.0*
ubuntu/linux-azure-fde*
ubuntu/linux-azure-fde-6.14*
ubuntu/linux-azure-fde-6.17*
ubuntu/linux-azure-fde-7.0*
ubuntu/linux-azure-nvidia*
ubuntu/linux-azure-nvidia-6.14*
ubuntu/linux-gcp*
ubuntu/linux-gcp-6.11*
ubuntu/linux-gcp-6.14*
ubuntu/linux-gcp-7.0*
ubuntu/linux-gke*
ubuntu/linux-gkeop*
ubuntu/linux-hwe-6.11*
ubuntu/linux-hwe-6.14*
ubuntu/linux-hwe-6.17*
ubuntu/linux-hwe-7.0<7.0.0-42.42~24.04.1
7.0.0-42.42~24.04.1
ubuntu/linux-ibm*
ubuntu/linux-lowlatency*
ubuntu/linux-lowlatency-hwe-6.11*
ubuntu/linux-nvidia*
ubuntu/linux-nvidia-6.11*
ubuntu/linux-nvidia-6.17*
ubuntu/linux-nvidia-7.0*
ubuntu/linux-nvidia-lowlatency*
ubuntu/linux-nvidia-tegra*
ubuntu/linux-oem-6.11*
ubuntu/linux-oem-6.14*
ubuntu/linux-oem-6.17*
ubuntu/linux-oem-6.8*
ubuntu/linux-oracle*
ubuntu/linux-oracle-6.14*
ubuntu/linux-oracle-6.17*
ubuntu/linux-oracle-7.0*
ubuntu/linux-raspi*
ubuntu/linux-raspi-realtime*
ubuntu/linux-realtime*
ubuntu/linux-riscv*
ubuntu/linux-riscv-6.14*
ubuntu/linux-riscv-6.17*
ubuntu/linux-riscv-7.0<7.0.0-42.42.1~24.04.1
7.0.0-42.42.1~24.04.1
ubuntu/linux-xilinx*
ubuntu/linux-bluefield*
ubuntu/linux-raspi-realtime*
ubuntu/linux-realtime*
ubuntu/linux-realtime-6.14*
ubuntu/linux-realtime-6.17*
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux<7.0.0-42.42
7.0.0-42.42
ubuntu/linux-aws<7.0.0-1016.17
7.0.0-1016.17
ubuntu/linux-azure*
ubuntu/linux-azure-fde*
ubuntu/linux-gcp<7.0.0-1016.18
7.0.0-1016.18
ubuntu/linux-gke*
ubuntu/linux-ibm<7.0.0-1017.17
7.0.0-1017.17
ubuntu/linux-nvidia*
ubuntu/linux-nvidia-bos*
ubuntu/linux-oem-7.0<7.0.0-1017.17
7.0.0-1017.17
ubuntu/linux-oracle<7.0.0-1015.16
7.0.0-1015.16
ubuntu/linux-raspi*
ubuntu/linux-realtime*
ubuntu/linux-riscv<7.0.0-42.42.1
7.0.0-42.42.1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

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

    Fixed in 6.12.111-1
  2. Upgrade

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

    Fixed in 7.2.6-1
  3. Upgrade

    Upgrade debian/linux-6.12 to a version that resolves this vulnerability.

    Fixed in 6.12.111-1~deb12u1
  4. Upgrade

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

    Fixed in 6.1.191
  5. Upgrade

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

    Fixed in 6.6.160
  6. Upgrade

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

    Fixed in 6.12.110
  7. Upgrade

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

    Fixed in 6.18.52
  8. Upgrade

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

    Fixed in 7.2.6
  9. Upgrade

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

    Fixed in 6.12.115-2Fixed in 7.2.12-1Fixed in 7.2.15-1
  10. Upgrade

    Upgrade debian/linux-6.12 to a version that resolves this vulnerability.

    Fixed in 6.12.113-1~deb12u1
  11. Upgrade

    Upgrade ubuntu/linux-hwe-7.0 to a version that resolves this vulnerability.

    Fixed in 7.0.0-42.42~24.04.1
  12. Upgrade

    Upgrade ubuntu/linux-riscv-7.0 to a version that resolves this vulnerability.

    Fixed in 7.0.0-42.42.1~24.04.1
  13. Upgrade

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

    Fixed in 7.0.0-42.42
  14. Upgrade

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

    Fixed in 7.0.0-1016.17
  15. Upgrade

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

    Fixed in 7.0.0-1016.18
  16. Upgrade

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

    Fixed in 7.0.0-1017.17
  17. Upgrade

    Upgrade ubuntu/linux-oem-7.0 to a version that resolves this vulnerability.

    Fixed in 7.0.0-1017.17
  18. Upgrade

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

    Fixed in 7.0.0-1015.16
  19. Upgrade

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

    Fixed in 7.0.0-42.42.1
  20. Compensating control

    In ksmbd_session_register(), when xa_store(&conn->sessions, sess->id, sess) fails, remove the session from sessions_table and drop its table reference to prevent the session leak.

Event History

Sep 17, 2026
CVE Published
via MITRE·04:06 PM
Data Sourced
via MITRE·04:06 PM
Description
Data Sourced
via OSV·04:06 PM
DescriptionAffected Software
Data Sourced
via OSV·05:17 PM
Severity
Data Sourced
via NVD·05:17 PM
Description

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

What condition triggers the leaked session?

The leak occurs when ksmbd_session_register() calls xa_store() for a newly created SMB2 session and xa_store() fails. The session has already been added to sessions_table, and the failure path drops only one reference, leaving the table reference and the session allocated.

2

Which component is affected?

The affected component is the Linux kernel SMB server, ksmbd. The issue is in the SMB2 session-setup path.

3

What does the fix change?

The fix removes the session from sessions_table and drops its table reference when xa_store() fails, allowing the session to be freed.

Contact

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