CVE-2026-45962: ublk: Validate SQE128 flag before accessing the cmd

Published May 27, 2026
·
Updated

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

ublk: Validate SQE128 flag before accessing the cmd

ublkctrlcmddump() accesses (header )sqe->cmd before IOURINGFSQE128 flag check. This could cause out of boundary memory access.

Move the SQE128 flag check earlier in ublkctrluringcmd() to return -EINVAL immediately if the flag is not set.

Affected Software

154 affected componentsFixes available
Linux Linux kernel
Linux Linux kernel>=6.0<6.1.165
Linux Linux kernel>=6.2<6.6.128
Linux Linux kernel>=6.7<6.12.75
Linux Linux kernel>=6.13<6.18.14
Linux Linux kernel>=6.19<6.19.4
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-5.8*
ubuntu/linux-azure-5.11*
ubuntu/linux-azure-5.13*
ubuntu/linux-azure-5.8*
ubuntu/linux-azure-fde*
ubuntu/linux-gcp-5.11*
ubuntu/linux-gcp-5.13*
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-5.8*
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-allwinner-5.19*
ubuntu/linux-aws-5.19*
ubuntu/linux-aws-6.2*
ubuntu/linux-aws-6.5*
ubuntu/linux-aws-6.8<6.8.0-1060.63~22.04.1
6.8.0-1060.63~22.04.1
ubuntu/linux-azure-5.19*
ubuntu/linux-azure-6.2*
ubuntu/linux-azure-6.5*
ubuntu/linux-azure-6.8<6.8.0-1063.71~22.04.1
6.8.0-1063.71~22.04.1
ubuntu/linux-azure-fde-5.19*
ubuntu/linux-azure-fde-6.2*
ubuntu/linux-azure-fde-6.8<6.8.0-1062.69~22.04.1
6.8.0-1062.69~22.04.1
ubuntu/linux-gcp-5.19*
ubuntu/linux-gcp-6.2*
ubuntu/linux-gcp-6.5*
ubuntu/linux-gcp-6.8<6.8.0-1063.69~22.04.1
6.8.0-1063.69~22.04.1
ubuntu/linux-hwe-5.19*
ubuntu/linux-hwe-6.2*
ubuntu/linux-hwe-6.5*
ubuntu/linux-hwe-6.8<6.8.0-136.136~22.04.1
6.8.0-136.136~22.04.1
ubuntu/linux-ibm-6.8<6.8.0-1060.61~22.04.1
6.8.0-1060.61~22.04.1
ubuntu/linux-intel-iot-realtime*
ubuntu/linux-lowlatency-hwe-5.19*
ubuntu/linux-lowlatency-hwe-6.2*
ubuntu/linux-lowlatency-hwe-6.5*
ubuntu/linux-lowlatency-hwe-6.8<6.8.0-134.134.1~22.04.1
6.8.0-134.134.1~22.04.1
ubuntu/linux-nvidia-6.2*
ubuntu/linux-nvidia-6.5*
ubuntu/linux-nvidia-6.8<6.8.0-1058.61~22.04.1
6.8.0-1058.61~22.04.1
ubuntu/linux-oem-5.17*
ubuntu/linux-oem-6.0*
ubuntu/linux-oem-6.1*
ubuntu/linux-oem-6.5*
ubuntu/linux-oracle-6.5*
ubuntu/linux-oracle-6.8<6.8.0-1057.58~22.04.1
6.8.0-1057.58~22.04.1
ubuntu/linux-realtime*
ubuntu/linux-riscv*
ubuntu/linux-riscv-5.19*
ubuntu/linux-riscv-6.5*
ubuntu/linux-riscv-6.8<6.8.0-134.134~22.04.1
6.8.0-134.134~22.04.1
ubuntu/linux-starfive-5.19*
ubuntu/linux-starfive-6.2*
ubuntu/linux-starfive-6.5*
ubuntu/linux-realtime-6.8<6.8.1-1055.56~22.04.1
6.8.1-1055.56~22.04.1
ubuntu/linux<6.8.0-134.134
6.8.0-134.134
ubuntu/linux-aws<6.8.0-1060.63
6.8.0-1060.63
ubuntu/linux-aws-6.14*
ubuntu/linux-aws-6.17*
ubuntu/linux-azure<6.8.0-1063.71
6.8.0-1063.71
ubuntu/linux-azure-6.11*
ubuntu/linux-azure-6.14*
ubuntu/linux-azure-6.17*
ubuntu/linux-azure-fde<6.8.0-1062.69
6.8.0-1062.69
ubuntu/linux-azure-fde-6.14*
ubuntu/linux-azure-nvidia<6.8.0-1039.42
6.8.0-1039.42
ubuntu/linux-azure-nvidia-6.14*
ubuntu/linux-gcp<6.8.0-1063.69
6.8.0-1063.69
ubuntu/linux-gcp-6.11*
ubuntu/linux-gcp-6.14*
ubuntu/linux-gke<6.8.0-1058.64
6.8.0-1058.64
ubuntu/linux-gkeop<6.8.0-1045.48
6.8.0-1045.48
ubuntu/linux-hwe-6.11*
ubuntu/linux-hwe-6.14*
ubuntu/linux-hwe-6.17*
ubuntu/linux-ibm<6.8.0-1060.61
6.8.0-1060.61
ubuntu/linux-lowlatency<6.8.0-134.134.1
6.8.0-134.134.1
ubuntu/linux-lowlatency-hwe-6.11*
ubuntu/linux-nvidia<6.8.0-1058.61
6.8.0-1058.61
ubuntu/linux-nvidia-6.11*
ubuntu/linux-nvidia-6.17*
ubuntu/linux-nvidia-lowlatency<6.8.0-1058.61.1
6.8.0-1058.61.1
ubuntu/linux-nvidia-tegra<6.8.0-1029.30
6.8.0-1029.30
ubuntu/linux-oem-6.11*
ubuntu/linux-oem-6.14*
ubuntu/linux-oem-6.17*
ubuntu/linux-oem-6.8*
ubuntu/linux-oracle<6.8.0-1057.58
6.8.0-1057.58
ubuntu/linux-oracle-6.14*
ubuntu/linux-oracle-6.17*
ubuntu/linux-raspi<6.8.0-1060.64
6.8.0-1060.64
ubuntu/linux-raspi-realtime*
ubuntu/linux-realtime*
ubuntu/linux-riscv*
ubuntu/linux-riscv-6.14*
ubuntu/linux-riscv-6.17*
ubuntu/linux-xilinx<6.8.0-1032.33
6.8.0-1032.33
ubuntu/linux-bluefield<6.8.0-1026.30
6.8.0-1026.30
ubuntu/linux-raspi-realtime<6.8.0-2049.50
6.8.0-2049.50
ubuntu/linux-realtime<6.8.1-1055.56
6.8.1-1055.56
ubuntu/linux-realtime-6.14*
ubuntu/linux-realtime-6.17*
ubuntu/linux-aws-fips<6.8.0-1060.63+fips1
6.8.0-1060.63+fips1
ubuntu/linux-azure-fips<6.8.0-1062.69+fips1
6.8.0-1062.69+fips1
ubuntu/linux-fips<6.8.0-134.134+fips1
6.8.0-134.134+fips1
ubuntu/linux-gcp-fips<6.8.0-1063.69+fips1
6.8.0-1063.69+fips1
ubuntu/linux*
ubuntu/linux-aws*
ubuntu/linux-azure*
ubuntu/linux-azure-fde*
ubuntu/linux-gcp*
ubuntu/linux-oracle*
ubuntu/linux-raspi*
ubuntu/linux-realtime*
ubuntu/linux-riscv*

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 6.8.0-1060.63~22.04.1
  2. Upgrade

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

    Fixed in 6.8.0-1063.71~22.04.1
  3. Upgrade

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

    Fixed in 6.8.0-1062.69~22.04.1
  4. Upgrade

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

    Fixed in 6.8.0-1063.69~22.04.1
  5. Upgrade

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

    Fixed in 6.8.0-136.136~22.04.1
  6. Upgrade

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

    Fixed in 6.8.0-1060.61~22.04.1
  7. Upgrade

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

    Fixed in 6.8.0-134.134.1~22.04.1
  8. Upgrade

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

    Fixed in 6.8.0-1058.61~22.04.1
  9. Upgrade

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

    Fixed in 6.8.0-1057.58~22.04.1
  10. Upgrade

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

    Fixed in 6.8.0-134.134~22.04.1
  11. Upgrade

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

    Fixed in 6.8.1-1055.56~22.04.1
  12. Upgrade

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

    Fixed in 6.8.0-134.134
  13. Upgrade

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

    Fixed in 6.8.0-1060.63
  14. Upgrade

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

    Fixed in 6.8.0-1063.71
  15. Upgrade

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

    Fixed in 6.8.0-1062.69
  16. Upgrade

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

    Fixed in 6.8.0-1039.42
  17. Upgrade

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

    Fixed in 6.8.0-1063.69
  18. Upgrade

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

    Fixed in 6.8.0-1058.64
  19. Upgrade

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

    Fixed in 6.8.0-1045.48
  20. Upgrade

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

    Fixed in 6.8.0-1060.61
  21. Upgrade

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

    Fixed in 6.8.0-134.134.1
  22. Upgrade

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

    Fixed in 6.8.0-1058.61
  23. Upgrade

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

    Fixed in 6.8.0-1058.61.1
  24. Upgrade

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

    Fixed in 6.8.0-1029.30
  25. Upgrade

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

    Fixed in 6.8.0-1057.58
  26. Upgrade

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

    Fixed in 6.8.0-1060.64
  27. Upgrade

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

    Fixed in 6.8.0-1032.33
  28. Upgrade

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

    Fixed in 6.8.0-1026.30
  29. Upgrade

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

    Fixed in 6.8.0-2049.50
  30. Upgrade

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

    Fixed in 6.8.1-1055.56
  31. Upgrade

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

    Fixed in 6.8.0-1060.63+fips1
  32. Upgrade

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

    Fixed in 6.8.0-1062.69+fips1
  33. Upgrade

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

    Fixed in 6.8.0-134.134+fips1
  34. Upgrade

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

    Fixed in 6.8.0-1063.69+fips1
  35. Compensating control

    In ublk_ctrl_uring_cmd(), validate that the IO_URING_F_SQE128 flag is set before accessing sqe->cmd; if it is not set, return -EINVAL immediately.

Event History

May 27, 2026
CVE Published
via MITRE·12:18 PM
Data Sourced
via MITRE·12:18 PM
Description
Data Sourced
via OSV·02:17 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·02:17 PM
RemedyDescriptionSeverityAffected Software

Frequently Asked Questions

1

What level of access does an attacker need?

Exposure requires local access and low-privilege access to the affected system, according to the CVSS vector. No user interaction is required.

2

What condition triggers the issue?

The vulnerable path is reached when ublk control command handling accesses the command data before verifying that the IO_URING_F_SQE128 flag is set. Requests without that flag can trigger an out-of-bounds memory access.

3

What does the fix change?

The fix moves the IO_URING_F_SQE128 validation earlier in ublk_ctrl_uring_cmd(), causing requests without the flag to fail immediately with -EINVAL before command data is accessed.

Company

Resources

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