CVE-2025-21945: ksmbd: fix use-after-free in smb2_lock

Published Apr 1, 2025
·
Updated

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

ksmbd: fix use-after-free in smb2lock

If smblock->zerolen has value, ->llist of smblock is not delete and flock is old one. It will cause use-after-free on 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
DescriptionSeverity
Data Sourced
via OSV·04:15 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·04:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
May 5, 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-2025-21945?

CVE-2025-21945 is considered a moderate severity vulnerability due to the potential for use-after-free errors in the Linux kernel.

2

How do I fix CVE-2025-21945?

To fix CVE-2025-21945, upgrade to the patched version of the Linux kernel where this vulnerability has been resolved.

3

What components of the Linux kernel are affected by CVE-2025-21945?

CVE-2025-21945 specifically affects the ksmbd component of the Linux kernel.

4

What could happen if CVE-2025-21945 is exploited?

If exploited, CVE-2025-21945 could lead to a use-after-free vulnerability, potentially allowing for privilege escalation or system instability.

5

When was CVE-2025-21945 disclosed?

CVE-2025-21945 was publicly disclosed as a vulnerability in the Linux kernel related to the ksmbd file server.

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