UBUNTU-CVE-2025-68817: Use After Free

Q: Which systems are in scope?

The affected software list includes Ubuntu linux, linux-realtime, linux-azure, linux-gcp, linux-azure-fde, linux-riscv, linux-gke, and linux-gkeop packages. The issue is in the kernel ksmbd tree-connection handling path and is triggered under high concurrency.

Q: What does exploitation require?

The vulnerability is network-reachable and has low attack complexity. It requires low privileges, has an attack prerequisite, and does not require user interaction.

Q: What is the potential impact?

Successful exploitation can have high impact on confidentiality, integrity, and availability. The weakness is a use-after-free caused when a tree-connection object is freed during disconnect processing while another concurrent path still references it.

Published Jan 13, 2026

Updated

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free in ksmbdtreeconnectput under concurrency Under high concurrency, A tree-connection object (tcon) is freed on a disconnect path while another path still holds a reference and later executes put()/write on it.

Affected Software

184 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<5.15.0-1105.112~20.04.1

5.15.0-1105.112~20.04.1

ubuntu/linux-aws-5.8*

ubuntu/linux-azure-5.11*

ubuntu/linux-azure-5.13*

ubuntu/linux-azure-5.15<5.15.0-1110.119~20.04.1

5.15.0-1110.119~20.04.1

ubuntu/linux-azure-5.8*

ubuntu/linux-azure-fde*

ubuntu/linux-gcp-5.11*

ubuntu/linux-gcp-5.13*

ubuntu/linux-gcp-5.15<5.15.0-1106.115~20.04.1

5.15.0-1106.115~20.04.1

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<5.15.0-176.186~20.04.1

5.15.0-176.186~20.04.1

ubuntu/linux-hwe-5.8*

ubuntu/linux-ibm-5.15<5.15.0-1099.102~20.04.1

5.15.0-1099.102~20.04.1

ubuntu/linux-intel-5.13*

ubuntu/linux-intel-iotg-5.15<5.15.0-1100.106~20.04.1

5.15.0-1100.106~20.04.1

ubuntu/linux-lowlatency-hwe-5.15<5.15.0-175.185~20.04.1

5.15.0-175.185~20.04.1

ubuntu/linux-nvidia-tegra-5.15<5.15.0-1057.57~20.04.1

5.15.0-1057.57~20.04.1

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<5.15.0-1102.108~20.04.1

5.15.0-1102.108~20.04.1

ubuntu/linux-oracle-5.8*

ubuntu/linux-raspi2*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.11*

ubuntu/linux-riscv-5.15<5.15.0-1099.103~20.04.1

5.15.0-1099.103~20.04.1

ubuntu/linux-riscv-5.8*

ubuntu/linux<5.15.0-176.186

5.15.0-176.186

ubuntu/linux-allwinner-5.19*

ubuntu/linux-aws<5.15.0-1105.112

5.15.0-1105.112

ubuntu/linux-aws-5.19*

ubuntu/linux-aws-6.2*

ubuntu/linux-aws-6.5*

ubuntu/linux-aws-6.8<6.8.0-1052.55~22.04.1

6.8.0-1052.55~22.04.1

ubuntu/linux-azure<5.15.0-1110.119

5.15.0-1110.119

ubuntu/linux-azure-5.19*

ubuntu/linux-azure-6.2*

ubuntu/linux-azure-6.5*

ubuntu/linux-azure-6.8<6.8.0-1059.65~22.04.1

6.8.0-1059.65~22.04.1

ubuntu/linux-azure-fde<5.15.0-1114.123

5.15.0-1114.123

ubuntu/linux-azure-fde-5.19*

ubuntu/linux-azure-fde-6.2*

ubuntu/linux-azure-fde-6.8<6.8.0-1058.65~22.04.1

6.8.0-1058.65~22.04.1

ubuntu/linux-gcp<5.15.0-1105.114

5.15.0-1105.114

ubuntu/linux-gcp-5.19*

ubuntu/linux-gcp-6.2*

ubuntu/linux-gcp-6.5*

ubuntu/linux-gcp-6.8<6.8.0-1054.57~22.04.1

6.8.0-1054.57~22.04.1

ubuntu/linux-gke<5.15.0-1101.107

5.15.0-1101.107

ubuntu/linux-gkeop<5.15.0-1088.96

5.15.0-1088.96

ubuntu/linux-hwe-5.19*

ubuntu/linux-hwe-6.2*

ubuntu/linux-hwe-6.5*

ubuntu/linux-hwe-6.8<6.8.0-110.110~22.04.1

6.8.0-110.110~22.04.1

ubuntu/linux-ibm<5.15.0-1099.102

5.15.0-1099.102

ubuntu/linux-ibm-6.8<6.8.0-1051.51~22.04.1

6.8.0-1051.51~22.04.1

ubuntu/linux-intel-iot-realtime*

ubuntu/linux-intel-iotg<5.15.0-1100.106

5.15.0-1100.106

ubuntu/linux-kvm<5.15.0-1097.102

5.15.0-1097.102

ubuntu/linux-lowlatency<5.15.0-175.185

5.15.0-175.185

ubuntu/linux-lowlatency-hwe-5.19*

ubuntu/linux-lowlatency-hwe-6.2*

ubuntu/linux-lowlatency-hwe-6.5*

ubuntu/linux-lowlatency-hwe-6.8<6.8.0-110.110.1~22.04.1

6.8.0-110.110.1~22.04.1

ubuntu/linux-nvidia<5.15.0-1100.101

5.15.0-1100.101

ubuntu/linux-nvidia-6.2*

ubuntu/linux-nvidia-6.5*

ubuntu/linux-nvidia-6.8<6.8.0-1051.54~22.04.1

6.8.0-1051.54~22.04.1

ubuntu/linux-nvidia-tegra<5.15.0-1057.57

5.15.0-1057.57

ubuntu/linux-nvidia-tegra-igx<5.15.0-1046.46

5.15.0-1046.46

ubuntu/linux-oem-5.17*

ubuntu/linux-oem-6.0*

ubuntu/linux-oem-6.1*

ubuntu/linux-oem-6.5*

ubuntu/linux-oracle<5.15.0-1102.108

5.15.0-1102.108

ubuntu/linux-oracle-6.5*

ubuntu/linux-oracle-6.8<6.8.0-1049.50~22.04.1

6.8.0-1049.50~22.04.1

ubuntu/linux-raspi<5.15.0-1099.102

5.15.0-1099.102

ubuntu/linux-realtime*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.19*

ubuntu/linux-riscv-6.5*

ubuntu/linux-riscv-6.8<6.8.0-110.110~22.04.1

6.8.0-110.110~22.04.1

ubuntu/linux-starfive-5.19*

ubuntu/linux-starfive-6.2*

ubuntu/linux-starfive-6.5*

ubuntu/linux-xilinx-zynqmp<5.15.0-1070.74

5.15.0-1070.74

ubuntu/linux-bluefield<5.15.0-1089.91

5.15.0-1089.91

ubuntu/linux-intel-iot-realtime<5.15.0-1097.99

5.15.0-1097.99

ubuntu/linux-realtime<5.15.0-1104.113

5.15.0-1104.113

ubuntu/linux-realtime-6.8<6.8.1-1047.48~22.04.1

6.8.1-1047.48~22.04.1

ubuntu/linux-aws-fips<5.15.0-1105.112+fips1

5.15.0-1105.112+fips1

ubuntu/linux-azure-fips<5.15.0-1110.119+fips1

5.15.0-1110.119+fips1

ubuntu/linux-fips<5.15.0-176.186+fips1

5.15.0-176.186+fips1

ubuntu/linux-gcp-fips<5.15.0-1105.114+fips1

5.15.0-1105.114+fips1

ubuntu/linux<6.8.0-110.110

6.8.0-110.110

ubuntu/linux-aws<6.8.0-1052.55

6.8.0-1052.55

ubuntu/linux-aws-6.14*

ubuntu/linux-aws-6.17<6.17.0-1012.12~24.04.1

6.17.0-1012.12~24.04.1

ubuntu/linux-azure<6.8.0-1054.60

6.8.0-1054.60

ubuntu/linux-azure-6.11*

ubuntu/linux-azure-6.14*

ubuntu/linux-azure-6.17<6.17.0-1013.13~24.04.1

6.17.0-1013.13~24.04.1

ubuntu/linux-azure-fde<6.8.0-1058.65

6.8.0-1058.65

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<6.8.0-1054.57

6.8.0-1054.57

ubuntu/linux-gcp-6.11*

ubuntu/linux-gcp-6.14*

ubuntu/linux-gcp-6.17<6.17.0-1012.12~24.04.1

6.17.0-1012.12~24.04.1

ubuntu/linux-gke<6.8.0-1050.56

6.8.0-1050.56

ubuntu/linux-gkeop<6.8.0-1037.40

6.8.0-1037.40

ubuntu/linux-hwe-6.11*

ubuntu/linux-hwe-6.14*

ubuntu/linux-hwe-6.17<6.17.0-22.22~24.04.1

6.17.0-22.22~24.04.1

ubuntu/linux-ibm<6.8.0-1051.51

6.8.0-1051.51

ubuntu/linux-lowlatency<6.8.0-110.110.1

6.8.0-110.110.1

ubuntu/linux-lowlatency-hwe-6.11*

ubuntu/linux-nvidia<6.8.0-1051.54

6.8.0-1051.54

ubuntu/linux-nvidia-6.11*

ubuntu/linux-nvidia-6.17<6.17.0-1018.18

6.17.0-1018.18

ubuntu/linux-nvidia-lowlatency<6.8.0-1051.54.1

6.8.0-1051.54.1

ubuntu/linux-nvidia-tegra<6.8.0-1022.22

6.8.0-1022.22

ubuntu/linux-oem-6.11*

ubuntu/linux-oem-6.14*

ubuntu/linux-oem-6.17<6.17.0-1020.20

6.17.0-1020.20

ubuntu/linux-oem-6.8*

ubuntu/linux-oracle<6.8.0-1049.50

6.8.0-1049.50

ubuntu/linux-oracle-6.14*

ubuntu/linux-oracle-6.17<6.17.0-1011.11~24.04.1

6.17.0-1011.11~24.04.1

ubuntu/linux-raspi<6.8.0-1052.56

6.8.0-1052.56

ubuntu/linux-raspi-realtime*

ubuntu/linux-realtime*

ubuntu/linux-riscv*

ubuntu/linux-riscv-6.14*

ubuntu/linux-riscv-6.17<6.17.0-22.22.1~24.04.1

6.17.0-22.22.1~24.04.1

ubuntu/linux-xilinx<6.8.0-1028.29

6.8.0-1028.29

ubuntu/linux-bluefield<6.8.0-1017.21

6.8.0-1017.21

ubuntu/linux-raspi-realtime<6.8.0-2042.43

6.8.0-2042.43

ubuntu/linux-realtime<6.8.1-1047.48

6.8.1-1047.48

ubuntu/linux-realtime-6.14*

ubuntu/linux-realtime-6.17<6.17.0-1010.11~24.04.1

6.17.0-1010.11~24.04.1

ubuntu/linux-aws-fips<6.8.0-1052.55+fips1

6.8.0-1052.55+fips1

ubuntu/linux-azure-fips<6.8.0-1053.59+fips1

6.8.0-1053.59+fips1

ubuntu/linux-fips<6.8.0-110.110+fips2

6.8.0-110.110+fips2

ubuntu/linux-gcp-fips<6.8.0-1054.57+fips1

6.8.0-1054.57+fips1

ubuntu/linux<6.17.0-22.22

6.17.0-22.22

ubuntu/linux-aws<6.17.0-1012.12

6.17.0-1012.12

ubuntu/linux-azure<6.17.0-1013.13

6.17.0-1013.13

ubuntu/linux-azure-fde*

ubuntu/linux-gcp<6.17.0-1012.12

6.17.0-1012.12

ubuntu/linux-oracle<6.17.0-1011.11

6.17.0-1011.11

ubuntu/linux-raspi<6.17.0-1013.13

6.17.0-1013.13

ubuntu/linux-realtime<6.17.0-1010.11

6.17.0-1010.11

ubuntu/linux-riscv<6.17.0-22.22.1

6.17.0-22.22.1

ubuntu/linux-vmware*

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 5.15.0-1105.112~20.04.1
Upgrade
Upgrade ubuntu/linux-azure-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1110.119~20.04.1
Upgrade
Upgrade ubuntu/linux-gcp-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1106.115~20.04.1
Upgrade
Upgrade ubuntu/linux-hwe-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-176.186~20.04.1
Upgrade
Upgrade ubuntu/linux-ibm-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1099.102~20.04.1
Upgrade
Upgrade ubuntu/linux-intel-iotg-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1100.106~20.04.1
Upgrade
Upgrade ubuntu/linux-lowlatency-hwe-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-175.185~20.04.1
Upgrade
Upgrade ubuntu/linux-nvidia-tegra-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1057.57~20.04.1
Upgrade
Upgrade ubuntu/linux-oracle-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1102.108~20.04.1
Upgrade
Upgrade ubuntu/linux-riscv-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1099.103~20.04.1
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 5.15.0-176.186
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 5.15.0-1105.112
Upgrade
Upgrade ubuntu/linux-aws-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1052.55~22.04.1
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 5.15.0-1110.119
Upgrade
Upgrade ubuntu/linux-azure-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1059.65~22.04.1
Upgrade
Upgrade ubuntu/linux-azure-fde to a version that resolves this vulnerability.
Fixed in 5.15.0-1114.123
Upgrade
Upgrade ubuntu/linux-azure-fde-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1058.65~22.04.1
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 5.15.0-1105.114
Upgrade
Upgrade ubuntu/linux-gcp-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1054.57~22.04.1
Upgrade
Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.
Fixed in 5.15.0-1101.107
Upgrade
Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.
Fixed in 5.15.0-1088.96
Upgrade
Upgrade ubuntu/linux-hwe-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-110.110~22.04.1
Upgrade
Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.
Fixed in 5.15.0-1099.102
Upgrade
Upgrade ubuntu/linux-ibm-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1051.51~22.04.1
Upgrade
Upgrade ubuntu/linux-intel-iotg to a version that resolves this vulnerability.
Fixed in 5.15.0-1100.106
Upgrade
Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.
Fixed in 5.15.0-1097.102
Upgrade
Upgrade ubuntu/linux-lowlatency to a version that resolves this vulnerability.
Fixed in 5.15.0-175.185
Upgrade
Upgrade ubuntu/linux-lowlatency-hwe-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-110.110.1~22.04.1
Upgrade
Upgrade ubuntu/linux-nvidia to a version that resolves this vulnerability.
Fixed in 5.15.0-1100.101
Upgrade
Upgrade ubuntu/linux-nvidia-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1051.54~22.04.1
Upgrade
Upgrade ubuntu/linux-nvidia-tegra to a version that resolves this vulnerability.
Fixed in 5.15.0-1057.57
Upgrade
Upgrade ubuntu/linux-nvidia-tegra-igx to a version that resolves this vulnerability.
Fixed in 5.15.0-1046.46
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 5.15.0-1102.108
Upgrade
Upgrade ubuntu/linux-oracle-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1049.50~22.04.1
Upgrade
Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.
Fixed in 5.15.0-1099.102
Upgrade
Upgrade ubuntu/linux-riscv-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-110.110~22.04.1
Upgrade
Upgrade ubuntu/linux-xilinx-zynqmp to a version that resolves this vulnerability.
Fixed in 5.15.0-1070.74
Upgrade
Upgrade ubuntu/linux-bluefield to a version that resolves this vulnerability.
Fixed in 5.15.0-1089.91
Upgrade
Upgrade ubuntu/linux-intel-iot-realtime to a version that resolves this vulnerability.
Fixed in 5.15.0-1097.99
Upgrade
Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.
Fixed in 5.15.0-1104.113
Upgrade
Upgrade ubuntu/linux-realtime-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.1-1047.48~22.04.1
Upgrade
Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-1105.112+fips1
Upgrade
Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-1110.119+fips1
Upgrade
Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-176.186+fips1
Upgrade
Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-1105.114+fips1
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 6.8.0-110.110
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 6.8.0-1052.55
Upgrade
Upgrade ubuntu/linux-aws-6.17 to a version that resolves this vulnerability.
Fixed in 6.17.0-1012.12~24.04.1
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 6.8.0-1054.60
Upgrade
Upgrade ubuntu/linux-azure-6.17 to a version that resolves this vulnerability.
Fixed in 6.17.0-1013.13~24.04.1
Upgrade
Upgrade ubuntu/linux-azure-fde to a version that resolves this vulnerability.
Fixed in 6.8.0-1058.65
Upgrade
Upgrade ubuntu/linux-azure-nvidia to a version that resolves this vulnerability.
Fixed in 6.8.0-1039.42
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 6.8.0-1054.57
Upgrade
Upgrade ubuntu/linux-gcp-6.17 to a version that resolves this vulnerability.
Fixed in 6.17.0-1012.12~24.04.1
Upgrade
Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.
Fixed in 6.8.0-1050.56
Upgrade
Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.
Fixed in 6.8.0-1037.40
Upgrade
Upgrade ubuntu/linux-hwe-6.17 to a version that resolves this vulnerability.
Fixed in 6.17.0-22.22~24.04.1
Upgrade
Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.
Fixed in 6.8.0-1051.51
Upgrade
Upgrade ubuntu/linux-lowlatency to a version that resolves this vulnerability.
Fixed in 6.8.0-110.110.1
Upgrade
Upgrade ubuntu/linux-nvidia to a version that resolves this vulnerability.
Fixed in 6.8.0-1051.54
Upgrade
Upgrade ubuntu/linux-nvidia-6.17 to a version that resolves this vulnerability.
Fixed in 6.17.0-1018.18
Upgrade
Upgrade ubuntu/linux-nvidia-lowlatency to a version that resolves this vulnerability.
Fixed in 6.8.0-1051.54.1
Upgrade
Upgrade ubuntu/linux-nvidia-tegra to a version that resolves this vulnerability.
Fixed in 6.8.0-1022.22
Upgrade
Upgrade ubuntu/linux-oem-6.17 to a version that resolves this vulnerability.
Fixed in 6.17.0-1020.20
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 6.8.0-1049.50
Upgrade
Upgrade ubuntu/linux-oracle-6.17 to a version that resolves this vulnerability.
Fixed in 6.17.0-1011.11~24.04.1
Upgrade
Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.
Fixed in 6.8.0-1052.56
Upgrade
Upgrade ubuntu/linux-riscv-6.17 to a version that resolves this vulnerability.
Fixed in 6.17.0-22.22.1~24.04.1
Upgrade
Upgrade ubuntu/linux-xilinx to a version that resolves this vulnerability.
Fixed in 6.8.0-1028.29
Upgrade
Upgrade ubuntu/linux-bluefield to a version that resolves this vulnerability.
Fixed in 6.8.0-1017.21
Upgrade
Upgrade ubuntu/linux-raspi-realtime to a version that resolves this vulnerability.
Fixed in 6.8.0-2042.43
Upgrade
Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.
Fixed in 6.8.1-1047.48
Upgrade
Upgrade ubuntu/linux-realtime-6.17 to a version that resolves this vulnerability.
Fixed in 6.17.0-1010.11~24.04.1
Upgrade
Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.
Fixed in 6.8.0-1052.55+fips1
Upgrade
Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.
Fixed in 6.8.0-1053.59+fips1
Upgrade
Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.
Fixed in 6.8.0-110.110+fips2
Upgrade
Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.
Fixed in 6.8.0-1054.57+fips1
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 6.17.0-22.22
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 6.17.0-1012.12
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 6.17.0-1013.13
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 6.17.0-1012.12
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 6.17.0-1011.11
Upgrade
Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.
Fixed in 6.17.0-1013.13
Upgrade
Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.
Fixed in 6.17.0-1010.11
Upgrade
Upgrade ubuntu/linux-riscv to a version that resolves this vulnerability.
Fixed in 6.17.0-22.22.1

Event History

Jan 13, 2026

CVE Published

via OSV·04:16 PM

Data Sourced

via OSV·04:16 PM

DescriptionSeverityAffected Software

Frequently Asked Questions

Which systems are in scope?

The affected software list includes Ubuntu linux, linux-realtime, linux-azure, linux-gcp, linux-azure-fde, linux-riscv, linux-gke, and linux-gkeop packages. The issue is in the kernel ksmbd tree-connection handling path and is triggered under high concurrency.

What does exploitation require?

The vulnerability is network-reachable and has low attack complexity. It requires low privileges, has an attack prerequisite, and does not require user interaction.

What is the potential impact?

Successful exploitation can have high impact on confidentiality, integrity, and availability. The weakness is a use-after-free caused when a tree-connection object is freed during disconnect processing while another concurrent path still references it.

UBUNTU-CVE-2025-68817: Use After Free

Affected Software

Remediation

Event History

Frequently Asked Questions

Which systems are in scope?

What does exploitation require?

What is the potential impact?

Company

Resources

Contact

Frequently Asked Questions

Which systems are in scope?

What does exploitation require?

What is the potential impact?