UBUNTU-CVE-2024-46695: Medium severity ubuntu/linux vulnerability

Q: Which systems are exposed to this issue?

Systems acting as NFS clients are exposed when they access an NFS filesystem exported with root squashing enabled. The affected software list includes Ubuntu linux kernel packages and the listed cloud and FIPS kernel variants.

Q: What access does an attacker need?

The reported scenario requires root-level access on an NFS client. That user can change security labels on files in the root-squashed NFS filesystem because required SELinux or Smack permission checks are bypassed.

Q: How can I tell whether this is relevant to my environment?

Review whether affected Ubuntu kernel packages are in use and whether hosts mount NFS filesystems exported with root squashing. The issue is specifically relevant where SELinux or Smack security labels are used on those NFS filesystems.

Q: What changes after the fix is applied?

The fix uses a path that performs the applicable permission checks rather than bypassing them when setting a security context. It also causes NFS server delegation conflicts to be recalled when a client changes a file security label.

Published Sep 13, 2024

Updated

In the Linux kernel, the following vulnerability has been resolved: selinux,smack: don't bypass permissions check in inodesetsecctx hook Marek Gresko reports that the root user on an NFS client is able to change the security labels on files on an NFS filesystem that is exported with root squashing enabled. The end of the kerneldoc comment for vfssetxattrnoperm() states: This function requires the caller to lock the inode's imutex before it is executed. It also assumes that the caller will make the appropriate permission checks. nfsdsetattr() does do permissions checking via fhverify() and nfsdpermission(), but those don't do all the same permissions checks that are done by securityinodesetxattr() and its related LSM hooks do. Since nfsdsetattr() is the only consumer of securityinodesetsecctx(), simplest solution appears to be to replace the call to vfssetxattrnoperm() with a call to vfssetxattrlocked(). This fixes the above issue and has the added benefit of causing nfsd to recall conflicting delegations on a file when a client tries to change its security label.

Affected Software

196 affected componentsFixes available

ubuntu/linux*

ubuntu/linux-aws*

ubuntu/linux-azure*

ubuntu/linux-lts-xenial*

ubuntu/linux*

ubuntu/linux-aws*

ubuntu/linux-aws-hwe*

ubuntu/linux-azure*

ubuntu/linux-gcp*

ubuntu/linux-hwe*

ubuntu/linux-hwe-edge*

ubuntu/linux-kvm*

ubuntu/linux-oracle*

ubuntu/linux-fips*

ubuntu/linux*

ubuntu/linux-aws*

ubuntu/linux-aws-5.0*

ubuntu/linux-aws-5.3*

ubuntu/linux-aws-5.4*

ubuntu/linux-azure*

ubuntu/linux-azure-4.15*

ubuntu/linux-azure-5.3*

ubuntu/linux-azure-5.4*

ubuntu/linux-azure-edge*

ubuntu/linux-gcp*

ubuntu/linux-gcp-4.15*

ubuntu/linux-gcp-5.3*

ubuntu/linux-gcp-5.4*

ubuntu/linux-gke-4.15*

ubuntu/linux-gke-5.4*

ubuntu/linux-gkeop-5.4*

ubuntu/linux-hwe*

ubuntu/linux-hwe-5.4*

ubuntu/linux-hwe-edge*

ubuntu/linux-ibm-5.4*

ubuntu/linux-kvm*

ubuntu/linux-oem*

ubuntu/linux-oracle*

ubuntu/linux-oracle-5.0*

ubuntu/linux-oracle-5.3*

ubuntu/linux-oracle-5.4*

ubuntu/linux-raspi-5.4*

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-aws-5.15<5.15.0-1073.79~20.04.1

5.15.0-1073.79~20.04.1

ubuntu/linux-azure-5.15<5.15.0-1078.87~20.04.1

5.15.0-1078.87~20.04.1

ubuntu/linux-gcp-5.15<5.15.0-1072.80~20.04.1

5.15.0-1072.80~20.04.1

ubuntu/linux-hwe-5.15<5.15.0-127.137~20.04.1

5.15.0-127.137~20.04.1

ubuntu/linux-ibm-5.15<5.15.0-1066.69~20.04.1

5.15.0-1066.69~20.04.1

ubuntu/linux-intel-iotg-5.15<5.15.0-1071.77~20.04.1

5.15.0-1071.77~20.04.1

ubuntu/linux-lowlatency-hwe-5.15<5.15.0-127.137~20.04.1

5.15.0-127.137~20.04.1

ubuntu/linux-nvidia-tegra-5.15<5.15.0-1032.32~20.04.1

5.15.0-1032.32~20.04.1

ubuntu/linux-oracle-5.15<5.15.0-1071.77~20.04.1

5.15.0-1071.77~20.04.1

ubuntu/linux-riscv-5.15<5.15.0-1069.73~20.04.1

5.15.0-1069.73~20.04.1

ubuntu/linux*

ubuntu/linux-aws*

ubuntu/linux-aws-5.11*

ubuntu/linux-aws-5.13*

ubuntu/linux-aws-5.8*

ubuntu/linux-azure*

ubuntu/linux-azure-5.11*

ubuntu/linux-azure-5.13*

ubuntu/linux-azure-5.8*

ubuntu/linux-azure-fde*

ubuntu/linux-bluefield*

ubuntu/linux-gcp*

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-ibm*

ubuntu/linux-intel-5.13*

ubuntu/linux-iot*

ubuntu/linux-kvm*

ubuntu/linux-oem-5.10*

ubuntu/linux-oem-5.13*

ubuntu/linux-oem-5.6*

ubuntu/linux-oracle*

ubuntu/linux-oracle-5.11*

ubuntu/linux-oracle-5.13*

ubuntu/linux-oracle-5.8*

ubuntu/linux-raspi*

ubuntu/linux-raspi2*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.11*

ubuntu/linux-riscv-5.8*

ubuntu/linux-xilinx-zynqmp*

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<5.15.0-127.137

5.15.0-127.137

ubuntu/linux-allwinner-5.19*

ubuntu/linux-aws<5.15.0-1073.79

5.15.0-1073.79

ubuntu/linux-aws-5.19*

ubuntu/linux-aws-6.2*

ubuntu/linux-aws-6.5*

ubuntu/linux-aws-6.8<6.8.0-1020.22~22.04.1

6.8.0-1020.22~22.04.1

ubuntu/linux-azure<5.15.0-1078.87

5.15.0-1078.87

ubuntu/linux-azure-5.19*

ubuntu/linux-azure-6.2*

ubuntu/linux-azure-6.5*

ubuntu/linux-azure-6.8<6.8.0-1020.23~22.04.1

6.8.0-1020.23~22.04.1

ubuntu/linux-azure-fde<5.15.0-1078.87.1

5.15.0-1078.87.1

ubuntu/linux-azure-fde-5.19*

ubuntu/linux-azure-fde-6.2*

ubuntu/linux-gcp<5.15.0-1072.80

5.15.0-1072.80

ubuntu/linux-gcp-5.19*

ubuntu/linux-gcp-6.2*

ubuntu/linux-gcp-6.5*

ubuntu/linux-gcp-6.8<6.8.0-1019.21~22.04.1

6.8.0-1019.21~22.04.1

ubuntu/linux-gke<5.15.0-1070.76

5.15.0-1070.76

ubuntu/linux-gkeop<5.15.0-1056.63

5.15.0-1056.63

ubuntu/linux-hwe-5.19*

ubuntu/linux-hwe-6.2*

ubuntu/linux-hwe-6.5*

ubuntu/linux-hwe-6.8<6.8.0-50.51~22.04.1

6.8.0-50.51~22.04.1

ubuntu/linux-ibm<5.15.0-1066.69

5.15.0-1066.69

ubuntu/linux-ibm-6.8<6.8.0-1017.17~22.04.1

6.8.0-1017.17~22.04.1

ubuntu/linux-intel-iotg<5.15.0-1071.77

5.15.0-1071.77

ubuntu/linux-kvm<5.15.0-1070.75

5.15.0-1070.75

ubuntu/linux-lowlatency<5.15.0-127.137

5.15.0-127.137

ubuntu/linux-lowlatency-hwe-5.19*

ubuntu/linux-lowlatency-hwe-6.2*

ubuntu/linux-lowlatency-hwe-6.5*

ubuntu/linux-lowlatency-hwe-6.8<6.8.0-50.51.1~22.04.1

6.8.0-50.51.1~22.04.1

ubuntu/linux-nvidia<5.15.0-1068.69

5.15.0-1068.69

ubuntu/linux-nvidia-6.2*

ubuntu/linux-nvidia-6.5*

ubuntu/linux-nvidia-6.8<6.8.0-1019.21~22.04.1

6.8.0-1019.21~22.04.1

ubuntu/linux-nvidia-tegra<5.15.0-1032.32

5.15.0-1032.32

ubuntu/linux-nvidia-tegra-igx<5.15.0-1020.20

5.15.0-1020.20

ubuntu/linux-oem-5.17*

ubuntu/linux-oem-6.0*

ubuntu/linux-oem-6.1*

ubuntu/linux-oem-6.5*

ubuntu/linux-oracle<5.15.0-1071.77

5.15.0-1071.77

ubuntu/linux-oracle-6.5*

ubuntu/linux-oracle-6.8<6.8.0-1017.18~22.04.1

6.8.0-1017.18~22.04.1

ubuntu/linux-raspi<5.15.0-1066.69

5.15.0-1066.69

ubuntu/linux-realtime*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.19*

ubuntu/linux-riscv-6.5*

ubuntu/linux-riscv-6.8<6.8.0-50.51.1~22.04.1

6.8.0-50.51.1~22.04.1

ubuntu/linux-starfive-5.19*

ubuntu/linux-starfive-6.2*

ubuntu/linux-starfive-6.5*

ubuntu/linux-xilinx-zynqmp<5.15.0-1039.43

5.15.0-1039.43

ubuntu/linux-bluefield<5.15.0-1057.59

5.15.0-1057.59

ubuntu/linux-intel-iot-realtime<5.15.0-1066.68

5.15.0-1066.68

ubuntu/linux-realtime<5.15.0-1074.82

5.15.0-1074.82

ubuntu/linux-realtime-6.8<6.8.1-1013.14~22.04.1

6.8.1-1013.14~22.04.1

ubuntu/linux-aws-fips*

ubuntu/linux-azure-fips*

ubuntu/linux-fips*

ubuntu/linux-gcp-fips*

ubuntu/linux-aws-fips<5.15.0-1073.79+fips1

5.15.0-1073.79+fips1

ubuntu/linux-azure-fips<5.15.0-1078.87+fips1

5.15.0-1078.87+fips1

ubuntu/linux-fips<5.15.0-127.137+fips1

5.15.0-127.137+fips1

ubuntu/linux-gcp-fips<5.15.0-1072.80+fips1

5.15.0-1072.80+fips1

ubuntu/linux<6.8.0-50.51

6.8.0-50.51

ubuntu/linux-aws<6.8.0-1020.22

6.8.0-1020.22

ubuntu/linux-azure<6.8.0-1020.23

6.8.0-1020.23

ubuntu/linux-gcp<6.8.0-1019.21

6.8.0-1019.21

ubuntu/linux-gke<6.8.0-1015.19

6.8.0-1015.19

ubuntu/linux-gkeop<6.8.0-1002.4

6.8.0-1002.4

ubuntu/linux-ibm<6.8.0-1017.17

6.8.0-1017.17

ubuntu/linux-lowlatency<6.8.0-50.51.1

6.8.0-50.51.1

ubuntu/linux-nvidia<6.8.0-1019.21

6.8.0-1019.21

ubuntu/linux-nvidia-lowlatency<6.8.0-1019.21.1

6.8.0-1019.21.1

ubuntu/linux-oem-6.8<6.8.0-1018.18

6.8.0-1018.18

ubuntu/linux-oracle<6.8.0-1017.18

6.8.0-1017.18

ubuntu/linux-raspi<6.8.0-1016.18

6.8.0-1016.18

ubuntu/linux-riscv<6.8.0-50.51.1

6.8.0-50.51.1

ubuntu/linux-xilinx<6.8.0-1017.18

6.8.0-1017.18

ubuntu/linux-raspi-realtime<6.8.0-2015.16

6.8.0-2015.16

ubuntu/linux-realtime<6.8.1-1013.14

6.8.1-1013.14

ubuntu/linux-fips<6.8.0-78.78+fips1

6.8.0-78.78+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 5.15.0-1073.79~20.04.1
Upgrade
Upgrade ubuntu/linux-azure-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1078.87~20.04.1
Upgrade
Upgrade ubuntu/linux-gcp-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1072.80~20.04.1
Upgrade
Upgrade ubuntu/linux-hwe-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-127.137~20.04.1
Upgrade
Upgrade ubuntu/linux-ibm-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1066.69~20.04.1
Upgrade
Upgrade ubuntu/linux-intel-iotg-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1071.77~20.04.1
Upgrade
Upgrade ubuntu/linux-lowlatency-hwe-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-127.137~20.04.1
Upgrade
Upgrade ubuntu/linux-nvidia-tegra-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1032.32~20.04.1
Upgrade
Upgrade ubuntu/linux-oracle-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1071.77~20.04.1
Upgrade
Upgrade ubuntu/linux-riscv-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1069.73~20.04.1
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 5.15.0-127.137
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 5.15.0-1073.79
Upgrade
Upgrade ubuntu/linux-aws-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1020.22~22.04.1
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 5.15.0-1078.87
Upgrade
Upgrade ubuntu/linux-azure-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1020.23~22.04.1
Upgrade
Upgrade ubuntu/linux-azure-fde to a version that resolves this vulnerability.
Fixed in 5.15.0-1078.87.1
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 5.15.0-1072.80
Upgrade
Upgrade ubuntu/linux-gcp-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1019.21~22.04.1
Upgrade
Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.
Fixed in 5.15.0-1070.76
Upgrade
Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.
Fixed in 5.15.0-1056.63
Upgrade
Upgrade ubuntu/linux-hwe-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-50.51~22.04.1
Upgrade
Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.
Fixed in 5.15.0-1066.69
Upgrade
Upgrade ubuntu/linux-ibm-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1017.17~22.04.1
Upgrade
Upgrade ubuntu/linux-intel-iotg to a version that resolves this vulnerability.
Fixed in 5.15.0-1071.77
Upgrade
Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.
Fixed in 5.15.0-1070.75
Upgrade
Upgrade ubuntu/linux-lowlatency to a version that resolves this vulnerability.
Fixed in 5.15.0-127.137
Upgrade
Upgrade ubuntu/linux-lowlatency-hwe-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-50.51.1~22.04.1
Upgrade
Upgrade ubuntu/linux-nvidia to a version that resolves this vulnerability.
Fixed in 5.15.0-1068.69
Upgrade
Upgrade ubuntu/linux-nvidia-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1019.21~22.04.1
Upgrade
Upgrade ubuntu/linux-nvidia-tegra to a version that resolves this vulnerability.
Fixed in 5.15.0-1032.32
Upgrade
Upgrade ubuntu/linux-nvidia-tegra-igx to a version that resolves this vulnerability.
Fixed in 5.15.0-1020.20
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 5.15.0-1071.77
Upgrade
Upgrade ubuntu/linux-oracle-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1017.18~22.04.1
Upgrade
Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.
Fixed in 5.15.0-1066.69
Upgrade
Upgrade ubuntu/linux-riscv-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-50.51.1~22.04.1
Upgrade
Upgrade ubuntu/linux-xilinx-zynqmp to a version that resolves this vulnerability.
Fixed in 5.15.0-1039.43
Upgrade
Upgrade ubuntu/linux-bluefield to a version that resolves this vulnerability.
Fixed in 5.15.0-1057.59
Upgrade
Upgrade ubuntu/linux-intel-iot-realtime to a version that resolves this vulnerability.
Fixed in 5.15.0-1066.68
Upgrade
Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.
Fixed in 5.15.0-1074.82
Upgrade
Upgrade ubuntu/linux-realtime-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.1-1013.14~22.04.1
Upgrade
Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-1073.79+fips1
Upgrade
Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-1078.87+fips1
Upgrade
Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-127.137+fips1
Upgrade
Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-1072.80+fips1
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 6.8.0-50.51
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 6.8.0-1020.22
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 6.8.0-1020.23
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 6.8.0-1019.21
Upgrade
Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.
Fixed in 6.8.0-1015.19
Upgrade
Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.
Fixed in 6.8.0-1002.4
Upgrade
Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.
Fixed in 6.8.0-1017.17
Upgrade
Upgrade ubuntu/linux-lowlatency to a version that resolves this vulnerability.
Fixed in 6.8.0-50.51.1
Upgrade
Upgrade ubuntu/linux-nvidia to a version that resolves this vulnerability.
Fixed in 6.8.0-1019.21
Upgrade
Upgrade ubuntu/linux-nvidia-lowlatency to a version that resolves this vulnerability.
Fixed in 6.8.0-1019.21.1
Upgrade
Upgrade ubuntu/linux-oem-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1018.18
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 6.8.0-1017.18
Upgrade
Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.
Fixed in 6.8.0-1016.18
Upgrade
Upgrade ubuntu/linux-riscv to a version that resolves this vulnerability.
Fixed in 6.8.0-50.51.1
Upgrade
Upgrade ubuntu/linux-xilinx to a version that resolves this vulnerability.
Fixed in 6.8.0-1017.18
Upgrade
Upgrade ubuntu/linux-raspi-realtime to a version that resolves this vulnerability.
Fixed in 6.8.0-2015.16
Upgrade
Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.
Fixed in 6.8.1-1013.14
Upgrade
Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.
Fixed in 6.8.0-78.78+fips1

Event History

Sep 13, 2024

CVE Published

via OSV·06:15 AM

Data Sourced

via OSV·06:15 AM

DescriptionSeverityAffected Software

Frequently Asked Questions

Which systems are exposed to this issue?

Systems acting as NFS clients are exposed when they access an NFS filesystem exported with root squashing enabled. The affected software list includes Ubuntu linux kernel packages and the listed cloud and FIPS kernel variants.

What access does an attacker need?

The reported scenario requires root-level access on an NFS client. That user can change security labels on files in the root-squashed NFS filesystem because required SELinux or Smack permission checks are bypassed.

How can I tell whether this is relevant to my environment?

Review whether affected Ubuntu kernel packages are in use and whether hosts mount NFS filesystems exported with root squashing. The issue is specifically relevant where SELinux or Smack security labels are used on those NFS filesystems.

What changes after the fix is applied?

The fix uses a path that performs the applicable permission checks rather than bypassing them when setting a security context. It also causes NFS server delegation conflicts to be recalled when a client changes a file security label.

UBUNTU-CVE-2024-46695: Medium severity ubuntu/linux vulnerability

Affected Software

Remediation

Event History

Frequently Asked Questions

Which systems are exposed to this issue?

What access does an attacker need?

How can I tell whether this is relevant to my environment?

What changes after the fix is applied?

Company

Resources

Contact