UBUNTU-CVE-2025-21947: Race Condition

Q: Which systems are exposed to this issue?

Systems using the listed Ubuntu Linux kernel packages are potentially affected when the ksmbd SMB server functionality is in use. The affected package list includes linux-realtime, linux-azure, linux-gcp, linux-gke, linux-gkeop, linux-riscv, linux-aws-fips, and linux-azure-fips.

Q: What conditions are needed for exploitation?

The vulnerability involves a race between IPC requests associated with ksmbd login handling and the FSCTL_PIPE_TRANSCEIVE ioctl path. The supplied severity vector indicates network reachability, low privileges, no user interaction, high attack complexity, and an additional required attack condition.

Q: What is the likely impact of a successful exploit?

Incorrect IPC response delivery can cause type confusion between messages and access to unexpected areas of memory. The severity vector rates confidentiality, integrity, and availability impact as high.

Q: How can this issue be remediated?

Apply the Ubuntu kernel update that includes the upstream fix for CVE-2025-21947. The fix ensures ksmbd continues checking subsequent IPC responses after detecting a response type mismatch.

Published Apr 1, 2025

Updated

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix type confusion via race condition when using ipcmsgsendrequest req->handle is allocated using ksmbdacquireid(&ipcida), based on idaalloc. req->handle from ksmbdipcloginrequest and FSCTLPIPETRANSCEIVE ioctl can be same and it could lead to type confusion between messages, resulting in access to unexpected parts of memory after an incorrect delivery. ksmbd check type of ipc response but missing add continue to check next ipc reponse.

Affected Software

158 affected componentsFixes available

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<5.15.0-1119.126~20.04.1

5.15.0-1119.126~20.04.1

ubuntu/linux-aws-5.8*

ubuntu/linux-azure-5.11*

ubuntu/linux-azure-5.13*

ubuntu/linux-azure-5.15<5.15.0-1125.134~20.04.1

5.15.0-1125.134~20.04.1

ubuntu/linux-azure-5.8*

ubuntu/linux-azure-fde*

ubuntu/linux-azure-fde-5.15<5.15.0-1124.133~20.04.1

5.15.0-1124.133~20.04.1

ubuntu/linux-gcp-5.11*

ubuntu/linux-gcp-5.13*

ubuntu/linux-gcp-5.15<5.15.0-1120.130~20.04.1

5.15.0-1120.130~20.04.1

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<5.15.0-202.212~20.04.1

5.15.0-202.212~20.04.1

ubuntu/linux-hwe-5.8*

ubuntu/linux-ibm-5.15<5.15.0-1113.117~20.04.1

5.15.0-1113.117~20.04.1

ubuntu/linux-intel-5.13*

ubuntu/linux-intel-iotg-5.15<5.15.0-1114.120~20.04.1

5.15.0-1114.120~20.04.1

ubuntu/linux-lowlatency-hwe-5.15<5.15.0-197.207~20.04.1

5.15.0-197.207~20.04.1

ubuntu/linux-nvidia-tegra-5.15<5.15.0-1070.72~20.04.1

5.15.0-1070.72~20.04.1

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<5.15.0-1116.122~20.04.1

5.15.0-1116.122~20.04.1

ubuntu/linux-oracle-5.8*

ubuntu/linux-raspi2*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.11*

ubuntu/linux-riscv-5.15<5.15.0-1113.117~20.04.2

5.15.0-1113.117~20.04.2

ubuntu/linux-riscv-5.8*

ubuntu/linux<5.15.0-202.212

5.15.0-202.212

ubuntu/linux-allwinner-5.19*

ubuntu/linux-aws<5.15.0-1119.126

5.15.0-1119.126

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<5.15.0-1125.134

5.15.0-1125.134

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<5.15.0-1124.133

5.15.0-1124.133

ubuntu/linux-azure-fde-5.19*

ubuntu/linux-azure-fde-6.2*

ubuntu/linux-gcp<5.15.0-1120.130

5.15.0-1120.130

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<5.15.0-1115.121

5.15.0-1115.121

ubuntu/linux-gkeop<5.15.0-1102.110

5.15.0-1102.110

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<5.15.0-1113.117

5.15.0-1113.117

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<5.15.0-1114.120

5.15.0-1114.120

ubuntu/linux-kvm<5.15.0-1111.116

5.15.0-1111.116

ubuntu/linux-lowlatency<5.15.0-197.207

5.15.0-197.207

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<5.15.0-1114.115

5.15.0-1114.115

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<5.15.0-1070.72

5.15.0-1070.72

ubuntu/linux-nvidia-tegra-igx<5.15.0-1059.59

5.15.0-1059.59

ubuntu/linux-oem-5.17*

ubuntu/linux-oem-6.0*

ubuntu/linux-oem-6.1*

ubuntu/linux-oem-6.5*

ubuntu/linux-oracle<5.15.0-1116.122

5.15.0-1116.122

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<5.15.0-1103.105

5.15.0-1103.105

ubuntu/linux-intel-iot-realtime<5.15.0-1111.115

5.15.0-1111.115

ubuntu/linux-realtime<5.15.0-1118.127

5.15.0-1118.127

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<5.15.0-1119.126+fips1

5.15.0-1119.126+fips1

ubuntu/linux-azure-fips<5.15.0-1125.134+fips1

5.15.0-1125.134+fips1

ubuntu/linux-fips<5.15.0-202.212+fips1

5.15.0-202.212+fips1

ubuntu/linux-gcp-fips<5.15.0-1120.130+fips1

5.15.0-1120.130+fips1

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

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade ubuntu/linux-aws-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1119.126~20.04.1
Upgrade
Upgrade ubuntu/linux-azure-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1125.134~20.04.1
Upgrade
Upgrade ubuntu/linux-azure-fde-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1124.133~20.04.1
Upgrade
Upgrade ubuntu/linux-gcp-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1120.130~20.04.1
Upgrade
Upgrade ubuntu/linux-hwe-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-202.212~20.04.1
Upgrade
Upgrade ubuntu/linux-ibm-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1113.117~20.04.1
Upgrade
Upgrade ubuntu/linux-intel-iotg-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1114.120~20.04.1
Upgrade
Upgrade ubuntu/linux-lowlatency-hwe-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-197.207~20.04.1
Upgrade
Upgrade ubuntu/linux-nvidia-tegra-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1070.72~20.04.1
Upgrade
Upgrade ubuntu/linux-oracle-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1116.122~20.04.1
Upgrade
Upgrade ubuntu/linux-riscv-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1113.117~20.04.2
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 5.15.0-202.212
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 5.15.0-1119.126
Upgrade
Upgrade ubuntu/linux-aws-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1039.41~22.04.1
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 5.15.0-1125.134
Upgrade
Upgrade ubuntu/linux-azure-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1036.42~22.04.1
Upgrade
Upgrade ubuntu/linux-azure-fde to a version that resolves this vulnerability.
Fixed in 5.15.0-1124.133
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 5.15.0-1120.130
Upgrade
Upgrade ubuntu/linux-gcp-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1040.42~22.04.1
Upgrade
Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.
Fixed in 5.15.0-1115.121
Upgrade
Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.
Fixed in 5.15.0-1102.110
Upgrade
Upgrade ubuntu/linux-hwe-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-85.85~22.04.1
Upgrade
Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.
Fixed in 5.15.0-1113.117
Upgrade
Upgrade ubuntu/linux-ibm-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1037.37~22.04.1
Upgrade
Upgrade ubuntu/linux-intel-iotg to a version that resolves this vulnerability.
Fixed in 5.15.0-1114.120
Upgrade
Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.
Fixed in 5.15.0-1111.116
Upgrade
Upgrade ubuntu/linux-lowlatency to a version that resolves this vulnerability.
Fixed in 5.15.0-197.207
Upgrade
Upgrade ubuntu/linux-lowlatency-hwe-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-84.84.1~22.04.1
Upgrade
Upgrade ubuntu/linux-nvidia to a version that resolves this vulnerability.
Fixed in 5.15.0-1114.115
Upgrade
Upgrade ubuntu/linux-nvidia-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1039.42~22.04.1
Upgrade
Upgrade ubuntu/linux-nvidia-tegra to a version that resolves this vulnerability.
Fixed in 5.15.0-1070.72
Upgrade
Upgrade ubuntu/linux-nvidia-tegra-igx to a version that resolves this vulnerability.
Fixed in 5.15.0-1059.59
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 5.15.0-1116.122
Upgrade
Upgrade ubuntu/linux-oracle-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1037.38~22.04.1
Upgrade
Upgrade ubuntu/linux-riscv-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-84.84~22.04.1
Upgrade
Upgrade ubuntu/linux-bluefield to a version that resolves this vulnerability.
Fixed in 5.15.0-1103.105
Upgrade
Upgrade ubuntu/linux-intel-iot-realtime to a version that resolves this vulnerability.
Fixed in 5.15.0-1111.115
Upgrade
Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.
Fixed in 5.15.0-1118.127
Upgrade
Upgrade ubuntu/linux-realtime-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.1-1034.35~22.04.1
Upgrade
Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-1119.126+fips1
Upgrade
Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-1125.134+fips1
Upgrade
Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-202.212+fips1
Upgrade
Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-1120.130+fips1
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 6.8.0-84.84
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 6.8.0-1039.41
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 6.8.0-1038.44
Upgrade
Upgrade ubuntu/linux-azure-6.11 to a version that resolves this vulnerability.
Fixed in 6.11.0-1018.18~24.04.1
Upgrade
Upgrade ubuntu/linux-azure-nvidia to a version that resolves this vulnerability.
Fixed in 6.8.0-1025.27
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 6.8.0-1040.42
Upgrade
Upgrade ubuntu/linux-gcp-6.11 to a version that resolves this vulnerability.
Fixed in 6.11.0-1016.16~24.04.1
Upgrade
Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.
Fixed in 6.8.0-1036.40
Upgrade
Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.
Fixed in 6.8.0-1023.25
Upgrade
Upgrade ubuntu/linux-hwe-6.11 to a version that resolves this vulnerability.
Fixed in 6.11.0-28.28~24.04.1
Upgrade
Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.
Fixed in 6.8.0-1037.37
Upgrade
Upgrade ubuntu/linux-lowlatency to a version that resolves this vulnerability.
Fixed in 6.8.0-84.84.1
Upgrade
Upgrade ubuntu/linux-lowlatency-hwe-6.11 to a version that resolves this vulnerability.
Fixed in 6.11.0-1015.16~24.04.2
Upgrade
Upgrade ubuntu/linux-nvidia to a version that resolves this vulnerability.
Fixed in 6.8.0-1039.42
Upgrade
Upgrade ubuntu/linux-nvidia-6.11 to a version that resolves this vulnerability.
Fixed in 6.11.0-1012.12
Upgrade
Upgrade ubuntu/linux-nvidia-lowlatency to a version that resolves this vulnerability.
Fixed in 6.8.0-1039.42.1
Upgrade
Upgrade ubuntu/linux-nvidia-tegra to a version that resolves this vulnerability.
Fixed in 6.8.0-1010.10
Upgrade
Upgrade ubuntu/linux-oem-6.11 to a version that resolves this vulnerability.
Fixed in 6.11.0-1024.24
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 6.8.0-1037.38
Upgrade
Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.
Fixed in 6.8.0-1039.43
Upgrade
Upgrade ubuntu/linux-xilinx to a version that resolves this vulnerability.
Fixed in 6.8.0-1018.19
Upgrade
Upgrade ubuntu/linux-raspi-realtime to a version that resolves this vulnerability.
Fixed in 6.8.0-2030.31
Upgrade
Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.
Fixed in 6.8.1-1034.35
Upgrade
Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.
Fixed in 6.8.0-1039.41+fips1
Upgrade
Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.
Fixed in 6.8.0-1040.46+fips1
Upgrade
Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.
Fixed in 6.8.0-84.84+fips1
Upgrade
Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.
Fixed in 6.8.0-1040.42+fips1

Event History

Apr 1, 2025

CVE Published

via OSV·04:15 PM

Data Sourced

via OSV·04:15 PM

DescriptionSeverityAffected Software

Frequently Asked Questions

Which systems are exposed to this issue?

Systems using the listed Ubuntu Linux kernel packages are potentially affected when the ksmbd SMB server functionality is in use. The affected package list includes linux-realtime, linux-azure, linux-gcp, linux-gke, linux-gkeop, linux-riscv, linux-aws-fips, and linux-azure-fips.

What conditions are needed for exploitation?

The vulnerability involves a race between IPC requests associated with ksmbd login handling and the FSCTL_PIPE_TRANSCEIVE ioctl path. The supplied severity vector indicates network reachability, low privileges, no user interaction, high attack complexity, and an additional required attack condition.

What is the likely impact of a successful exploit?

Incorrect IPC response delivery can cause type confusion between messages and access to unexpected areas of memory. The severity vector rates confidentiality, integrity, and availability impact as high.

How can this issue be remediated?

Apply the Ubuntu kernel update that includes the upstream fix for CVE-2025-21947. The fix ensures ksmbd continues checking subsequent IPC responses after detecting a response type mismatch.

UBUNTU-CVE-2025-21947: Race Condition

Affected Software

Remediation

Event History

Frequently Asked Questions

Which systems are exposed to this issue?

What conditions are needed for exploitation?

What is the likely impact of a successful exploit?

How can this issue be remediated?

Company

Resources

Contact

Frequently Asked Questions

Which systems are exposed to this issue?

What conditions are needed for exploitation?

What is the likely impact of a successful exploit?

How can this issue be remediated?