CVE-2025-21944: ksmbd: fix bug on trap in smb2_lock

Published Apr 1, 2025
·
Updated

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

ksmbd: fix bug on trap in smb2lock

If lock count is greater than 1, flags could be old value. It should be checked with flags of smblock, not flags. It will cause bug-on trap from locksfreelock in error handling routine.

Affected Software

169 affected componentsFixes available
Linux Kernel
Linux Linux kernel>=5.15<6.1.131
Linux Linux kernel>=6.2<6.6.83
Linux Linux kernel>=6.7<6.12.19
Linux Linux kernel>=6.13<6.13.7
Linux Linux kernel=6.14-rc1
Linux Linux kernel=6.14-rc2
Linux Linux kernel=6.14-rc3
Linux Linux kernel=6.14-rc4
Linux Linux kernel=6.14-rc5
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<6.8.0-1039.41~22.04.1
6.8.0-1039.41~22.04.1
ubuntu/linux-azure*
ubuntu/linux-azure-5.19*
ubuntu/linux-azure-6.2*
ubuntu/linux-azure-6.5*
ubuntu/linux-azure-6.8<6.8.0-1036.42~22.04.1
6.8.0-1036.42~22.04.1
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<6.8.0-1040.42~22.04.1
6.8.0-1040.42~22.04.1
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<6.8.0-85.85~22.04.1
6.8.0-85.85~22.04.1
ubuntu/linux-ibm*
ubuntu/linux-ibm-6.8<6.8.0-1037.37~22.04.1
6.8.0-1037.37~22.04.1
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<6.8.0-84.84.1~22.04.1
6.8.0-84.84.1~22.04.1
ubuntu/linux-nvidia*
ubuntu/linux-nvidia-6.2*
ubuntu/linux-nvidia-6.5*
ubuntu/linux-nvidia-6.8<6.8.0-1039.42~22.04.1
6.8.0-1039.42~22.04.1
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<6.8.0-1037.38~22.04.1
6.8.0-1037.38~22.04.1
ubuntu/linux-raspi*
ubuntu/linux-realtime*
ubuntu/linux-riscv*
ubuntu/linux-riscv-5.19*
ubuntu/linux-riscv-6.5*
ubuntu/linux-riscv-6.8<6.8.0-84.84~22.04.1
6.8.0-84.84~22.04.1
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<6.8.1-1034.35~22.04.1
6.8.1-1034.35~22.04.1
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<6.8.0-84.84
6.8.0-84.84
ubuntu/linux-aws<6.8.0-1039.41
6.8.0-1039.41
ubuntu/linux-azure<6.8.0-1038.44
6.8.0-1038.44
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<6.8.0-1025.27
6.8.0-1025.27
ubuntu/linux-gcp<6.8.0-1040.42
6.8.0-1040.42
ubuntu/linux-gcp-6.11<6.11.0-1016.16~24.04.1
6.11.0-1016.16~24.04.1
ubuntu/linux-gke<6.8.0-1036.40
6.8.0-1036.40
ubuntu/linux-gkeop<6.8.0-1023.25
6.8.0-1023.25
ubuntu/linux-hwe-6.11<6.11.0-28.28~24.04.1
6.11.0-28.28~24.04.1
ubuntu/linux-ibm<6.8.0-1037.37
6.8.0-1037.37
ubuntu/linux-intel*
ubuntu/linux-lowlatency<6.8.0-84.84.1
6.8.0-84.84.1
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<6.8.0-1039.42
6.8.0-1039.42
ubuntu/linux-nvidia-6.11<6.11.0-1012.12
6.11.0-1012.12
ubuntu/linux-nvidia-lowlatency<6.8.0-1039.42.1
6.8.0-1039.42.1
ubuntu/linux-nvidia-tegra<6.8.0-1010.10
6.8.0-1010.10
ubuntu/linux-oem-6.11<6.11.0-1024.24
6.11.0-1024.24
ubuntu/linux-oem-6.8*
ubuntu/linux-oracle<6.8.0-1037.38
6.8.0-1037.38
ubuntu/linux-raspi<6.8.0-1039.43
6.8.0-1039.43
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-raspi-realtime<6.8.0-2030.31
6.8.0-2030.31
ubuntu/linux-realtime<6.8.1-1034.35
6.8.1-1034.35
ubuntu/linux-aws-fips<6.8.0-1039.41+fips1
6.8.0-1039.41+fips1
ubuntu/linux-azure-fips<6.8.0-1040.46+fips1
6.8.0-1040.46+fips1
ubuntu/linux-fips<6.8.0-84.84+fips1
6.8.0-84.84+fips1
ubuntu/linux-gcp-fips<6.8.0-1040.42+fips1
6.8.0-1040.42+fips1
debian/linux
6.1.176-16.1.190-16.12.107-16.12.115-27.2.12-17.2.15-1

Event History

Apr 1, 2025
CVE Published
via MITRE·03:41 PM
Data Sourced
via MITRE·03:41 PM
Description
Data Sourced
via OSV·04:15 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·04:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
Nov 1, 2025
Data Sourced
via Microsoft·01:02 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-2025-21944?

CVE-2025-21944 has been classified as a medium severity vulnerability in the Linux kernel.

2

How do I fix CVE-2025-21944?

To fix CVE-2025-21944, update your Linux kernel to the latest stable version that includes the security patch.

3

What impact does CVE-2025-21944 have on my system?

CVE-2025-21944 may lead to a bug-on trap during error handling related to lock counts in the Linux kernel's ksmbd.

4

Which versions of the Linux kernel are affected by CVE-2025-21944?

CVE-2025-21944 affects specific versions of the Linux kernel that utilize the ksmbd module, particularly prior to the patch release.

5

Is CVE-2025-21944 a remote exploit vulnerability?

CVE-2025-21944 does not appear to be a remote exploit vulnerability, but it can affect local processes related to file locking.

Contact

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