CVE-2026-23405: apparmor: fix: limit the number of levels of policy namespaces

Q: What is the severity of CVE-2026-23405?

CVE-2026-23405 has been classified with a moderate severity level due to its potential impact on policy namespace limitations.

Q: What systems are affected by CVE-2026-23405?

CVE-2026-23405 affects the Linux kernel specifically in relation to the AppArmor security module.

Q: How do I fix CVE-2026-23405?

To address CVE-2026-23405, ensure that your Linux kernel is updated to the latest version that patches this vulnerability.

Q: What is the nature of CVE-2026-23405?

CVE-2026-23405 is a vulnerability related to the lack of limits on the number of policy namespaces in the AppArmor component of the Linux kernel.

Q: When was CVE-2026-23405 addressed?

CVE-2026-23405 was resolved in recent updates to the Linux kernel, specifically related to AppArmor.

Published Apr 1, 2026

Updated

apparmor: fix: limit the number of levels of policy namespaces

Other sources

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

— Launchpad

Affected Software

262 affected componentsFixes available

Linux Linux kernel (AppArmor)

Microsoft azl3 kernel 6.6.0.0-1

Patch available

Linux Linux kernel>=2.6.36.1<5.10.253

Linux Linux kernel>=5.11<5.15.203

Linux Linux kernel>=5.16<6.1.169

Linux Linux kernel>=6.2<6.6.130

Linux Linux kernel>=6.7<6.12.77

Linux Linux kernel>=6.13<6.18.18

Linux Linux kernel>=6.19<6.19.8

Linux Linux kernel=2.6.36

Linux Linux kernel=7.0-rc1

Linux Linux kernel=7.0-rc2

Linux Linux kernel=7.0-rc3

Linux Linux kernel=7.0-rc4

Linux Linux kernel=7.0-rc5

Linux Linux kernel=7.0-rc6

Linux Linux kernel=7.0-rc7

debian/linux<=5.10.223-1

5.10.251-56.1.170-36.1.172-16.12.86-16.12.88-17.0.7-1

All of the following

azurelinux/kernel<6.6.130.1-1

6.6.130.1-1

Microsoft Azure Linux=3.0

ubuntu/linux*

ubuntu/linux-aws*

ubuntu/linux-azure<4.15.0-1200.215~14.04.1

4.15.0-1200.215~14.04.1

ubuntu/linux-lts-xenial*

ubuntu/linux-aws-hwe<4.15.0-1191.204~16.04.1

4.15.0-1191.204~16.04.1

ubuntu/linux-azure<4.15.0-1200.215~16.04.1

4.15.0-1200.215~16.04.1

ubuntu/linux-gcp<4.15.0-1184.201~16.04.1

4.15.0-1184.201~16.04.1

ubuntu/linux-hwe<4.15.0-249.261~16.04.1

4.15.0-249.261~16.04.1

ubuntu/linux-oracle<4.15.0-1153.164~16.04.1

4.15.0-1153.164~16.04.1

ubuntu/linux*

ubuntu/linux-aws*

ubuntu/linux-hwe-edge*

ubuntu/linux-kvm*

ubuntu/linux-fips*

ubuntu/linux<4.15.0-249.261

4.15.0-249.261

ubuntu/linux-aws<4.15.0-1191.204

4.15.0-1191.204

ubuntu/linux-aws-5.0*

ubuntu/linux-aws-5.3*

ubuntu/linux-aws-5.4<5.4.0-1156.166~18.04.1

5.4.0-1156.166~18.04.1

ubuntu/linux-azure*

ubuntu/linux-azure-4.15<4.15.0-1200.215

4.15.0-1200.215

ubuntu/linux-azure-5.3*

ubuntu/linux-azure-5.4<5.4.0-1161.167~18.04.1

5.4.0-1161.167~18.04.1

ubuntu/linux-azure-edge*

ubuntu/linux-gcp*

ubuntu/linux-gcp-4.15<4.15.0-1184.201

4.15.0-1184.201

ubuntu/linux-gcp-5.3*

ubuntu/linux-gcp-5.4<5.4.0-1159.168~18.04.1

5.4.0-1159.168~18.04.1

ubuntu/linux-gke-4.15*

ubuntu/linux-gke-5.4*

ubuntu/linux-gkeop-5.4*

ubuntu/linux-hwe*

ubuntu/linux-hwe-5.4<5.4.0-227.247~18.04.1

5.4.0-227.247~18.04.1

ubuntu/linux-hwe-edge*

ubuntu/linux-ibm-5.4<5.4.0-1102.107~18.04.1

5.4.0-1102.107~18.04.1

ubuntu/linux-kvm<4.15.0-1173.178

4.15.0-1173.178

ubuntu/linux-oem*

ubuntu/linux-oracle<4.15.0-1153.164

4.15.0-1153.164

ubuntu/linux-oracle-5.0*

ubuntu/linux-oracle-5.3*

ubuntu/linux-oracle-5.4<5.4.0-1154.164~18.04.1

5.4.0-1154.164~18.04.1

ubuntu/linux-raspi-5.4<5.4.0-1139.152~18.04.1

5.4.0-1139.152~18.04.1

ubuntu/linux-aws-fips<4.15.0-2129.135

4.15.0-2129.135

ubuntu/linux-azure-fips<4.15.0-2109.115

4.15.0-2109.115

ubuntu/linux-fips<4.15.0-1146.158

4.15.0-1146.158

ubuntu/linux-gcp-fips<4.15.0-2092.98

4.15.0-2092.98

ubuntu/linux-aws-fips*

ubuntu/linux-azure-fips*

ubuntu/linux-fips*

ubuntu/linux-gcp-fips*

ubuntu/linux<5.4.0-227.247

5.4.0-227.247

ubuntu/linux-aws<5.4.0-1156.166

5.4.0-1156.166

ubuntu/linux-aws-5.11*

ubuntu/linux-aws-5.13*

ubuntu/linux-aws-5.15<5.15.0-1103.110~20.04.1

5.15.0-1103.110~20.04.1

ubuntu/linux-aws-5.8*

ubuntu/linux-azure<5.4.0-1160.166

5.4.0-1160.166

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-bluefield<5.4.0-1116.123

5.4.0-1116.123

ubuntu/linux-gcp<5.4.0-1159.168

5.4.0-1159.168

ubuntu/linux-gcp-5.11*

ubuntu/linux-gcp-5.13*

ubuntu/linux-gcp-5.15<5.15.0-1103.112~20.04.1

5.15.0-1103.112~20.04.1

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<5.15.0-173.183~20.04.1

5.15.0-173.183~20.04.1

ubuntu/linux-hwe-5.8*

ubuntu/linux-ibm<5.4.0-1102.107

5.4.0-1102.107

ubuntu/linux-ibm-5.15<5.15.0-1097.100~20.04.1

5.15.0-1097.100~20.04.1

ubuntu/linux-intel-5.13*

ubuntu/linux-intel-iotg-5.15<5.15.0-1098.104~20.04.1

5.15.0-1098.104~20.04.1

ubuntu/linux-iot<5.4.0-1060.63

5.4.0-1060.63

ubuntu/linux-kvm<5.4.0-1143.152

5.4.0-1143.152

ubuntu/linux-lowlatency-hwe-5.15<5.15.0-173.183~20.04.1

5.15.0-173.183~20.04.1

ubuntu/linux-nvidia-tegra-5.15<5.15.0-1055.55~20.04.1

5.15.0-1055.55~20.04.1

ubuntu/linux-oem-5.10*

ubuntu/linux-oem-5.13*

ubuntu/linux-oem-5.6*

ubuntu/linux-oracle<5.4.0-1154.164

5.4.0-1154.164

ubuntu/linux-oracle-5.11*

ubuntu/linux-oracle-5.13*

ubuntu/linux-oracle-5.15<5.15.0-1100.106~20.04.1

5.15.0-1100.106~20.04.1

ubuntu/linux-oracle-5.8*

ubuntu/linux-raspi<5.4.0-1139.152

5.4.0-1139.152

ubuntu/linux-raspi2*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.11*

ubuntu/linux-riscv-5.15<5.15.0-1098.102~20.04.1

5.15.0-1098.102~20.04.1

ubuntu/linux-riscv-5.8*

ubuntu/linux-xilinx-zynqmp<5.4.0-1074.78

5.4.0-1074.78

ubuntu/linux-aws-fips<5.4.0-1156.166+fips1

5.4.0-1156.166+fips1

ubuntu/linux-azure-fips<5.4.0-1160.166+fips1

5.4.0-1160.166+fips1

ubuntu/linux-fips<5.4.0-1130.140

5.4.0-1130.140

ubuntu/linux-gcp-fips<5.4.0-1159.168+fips1

5.4.0-1159.168+fips1

ubuntu/linux-aws-fips*

ubuntu/linux-azure-fips*

ubuntu/linux-fips*

ubuntu/linux-gcp-fips*

ubuntu/linux<5.15.0-173.183

5.15.0-173.183

ubuntu/linux-allwinner-5.19*

ubuntu/linux-aws<5.15.0-1103.110

5.15.0-1103.110

ubuntu/linux-aws-5.19*

ubuntu/linux-aws-6.2*

ubuntu/linux-aws-6.5*

ubuntu/linux-aws-6.8<6.8.0-1050.53~22.04.1

6.8.0-1050.53~22.04.1

ubuntu/linux-azure<5.15.0-1109.118

5.15.0-1109.118

ubuntu/linux-azure-5.19*

ubuntu/linux-azure-6.2*

ubuntu/linux-azure-6.5*

ubuntu/linux-azure-6.8<6.8.0-1051.57~22.04.1

6.8.0-1051.57~22.04.1

ubuntu/linux-azure-fde<5.15.0-1109.118.1

5.15.0-1109.118.1

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<5.15.0-1103.112

5.15.0-1103.112

ubuntu/linux-gcp-5.19*

ubuntu/linux-gcp-6.2*

ubuntu/linux-gcp-6.5*

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

6.8.0-1052.55~22.04.1

ubuntu/linux-gke<5.15.0-1099.105

5.15.0-1099.105

ubuntu/linux-gkeop<5.15.0-1086.94

5.15.0-1086.94

ubuntu/linux-hwe-5.19*

ubuntu/linux-hwe-6.2*

ubuntu/linux-hwe-6.5*

ubuntu/linux-hwe-6.8<6.8.0-106.106~22.04.1

6.8.0-106.106~22.04.1

ubuntu/linux-ibm<5.15.0-1097.100

5.15.0-1097.100

ubuntu/linux-ibm-6.8<6.8.0-1049.49~22.04.1

6.8.0-1049.49~22.04.1

ubuntu/linux-intel-iot-realtime*

ubuntu/linux-intel-iotg<5.15.0-1098.104

5.15.0-1098.104

ubuntu/linux-kvm<5.15.0-1095.100

5.15.0-1095.100

ubuntu/linux-lowlatency<5.15.0-173.183

5.15.0-173.183

ubuntu/linux-lowlatency-hwe-5.19*

ubuntu/linux-lowlatency-hwe-6.2*

ubuntu/linux-lowlatency-hwe-6.5*

ubuntu/linux-lowlatency-hwe-6.8<6.8.0-106.106.1~22.04.1

6.8.0-106.106.1~22.04.1

ubuntu/linux-nvidia<5.15.0-1098.99

5.15.0-1098.99

ubuntu/linux-nvidia-6.2*

ubuntu/linux-nvidia-6.5*

ubuntu/linux-nvidia-6.8<6.8.0-1049.52~22.04.1

6.8.0-1049.52~22.04.1

ubuntu/linux-nvidia-tegra<5.15.0-1055.55

5.15.0-1055.55

ubuntu/linux-nvidia-tegra-igx<5.15.0-1044.44

5.15.0-1044.44

ubuntu/linux-oem-5.17*

ubuntu/linux-oem-6.0*

ubuntu/linux-oem-6.1*

ubuntu/linux-oem-6.5*

ubuntu/linux-oracle<5.15.0-1100.106

5.15.0-1100.106

ubuntu/linux-oracle-6.5*

ubuntu/linux-oracle-6.8<6.8.0-1047.48~22.04.1

6.8.0-1047.48~22.04.1

ubuntu/linux-raspi<5.15.0-1097.100

5.15.0-1097.100

ubuntu/linux-realtime*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.19*

ubuntu/linux-riscv-6.5*

ubuntu/linux-riscv-6.8<6.8.0-106.106~22.04.1

6.8.0-106.106~22.04.1

ubuntu/linux-starfive-5.19*

ubuntu/linux-starfive-6.2*

ubuntu/linux-starfive-6.5*

ubuntu/linux-xilinx-zynqmp<5.15.0-1067.71

5.15.0-1067.71

ubuntu/linux-bluefield<5.15.0-1087.89

5.15.0-1087.89

ubuntu/linux-intel-iot-realtime<5.15.0-1096.98

5.15.0-1096.98

ubuntu/linux-realtime<5.15.0-1102.111

5.15.0-1102.111

ubuntu/linux-realtime-6.8<6.8.1-1045.46~22.04.1

6.8.1-1045.46~22.04.1

ubuntu/linux-aws-fips*

ubuntu/linux-azure-fips*

ubuntu/linux-fips*

ubuntu/linux-gcp-fips*

ubuntu/linux-aws-fips<5.15.0-1103.110+fips1

5.15.0-1103.110+fips1

ubuntu/linux-azure-fips<5.15.0-1109.118+fips1

5.15.0-1109.118+fips1

ubuntu/linux-fips<5.15.0-173.183+fips1

5.15.0-173.183+fips1

ubuntu/linux-gcp-fips<5.15.0-1103.112+fips1

5.15.0-1103.112+fips1

ubuntu/linux<6.8.0-106.106

6.8.0-106.106

ubuntu/linux-aws<6.8.0-1050.53

6.8.0-1050.53

ubuntu/linux-aws-6.14*

ubuntu/linux-aws-6.17<6.17.0-1009.9~24.04.2

6.17.0-1009.9~24.04.2

ubuntu/linux-azure<6.8.0-1051.57

6.8.0-1051.57

ubuntu/linux-azure-6.11*

ubuntu/linux-azure-6.14*

ubuntu/linux-azure-6.17<6.17.0-1010.10~24.04.1

6.17.0-1010.10~24.04.1

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<6.8.0-1052.55

6.8.0-1052.55

ubuntu/linux-gcp-6.11*

ubuntu/linux-gcp-6.14*

ubuntu/linux-gcp-6.17<6.17.0-1009.9~24.04.3

6.17.0-1009.9~24.04.3

ubuntu/linux-gke<6.8.0-1048.53

6.8.0-1048.53

ubuntu/linux-gkeop<6.8.0-1035.38

6.8.0-1035.38

ubuntu/linux-hwe-6.11*

ubuntu/linux-hwe-6.14*

ubuntu/linux-hwe-6.17<6.17.0-19.19~24.04.2

6.17.0-19.19~24.04.2

ubuntu/linux-ibm<6.8.0-1049.49

6.8.0-1049.49

ubuntu/linux-lowlatency<6.8.0-106.106.1

6.8.0-106.106.1

ubuntu/linux-lowlatency-hwe-6.11*

ubuntu/linux-nvidia<6.8.0-1049.52

6.8.0-1049.52

ubuntu/linux-nvidia-6.11*

ubuntu/linux-nvidia-6.17<6.17.0-1014.14

6.17.0-1014.14

ubuntu/linux-nvidia-lowlatency<6.8.0-1049.52.1

6.8.0-1049.52.1

ubuntu/linux-nvidia-tegra<6.8.0-1020.20

6.8.0-1020.20

ubuntu/linux-oem-6.11*

ubuntu/linux-oem-6.14*

ubuntu/linux-oem-6.17<6.17.0-1017.17

6.17.0-1017.17

ubuntu/linux-oem-6.8*

ubuntu/linux-oracle<6.8.0-1047.48

6.8.0-1047.48

ubuntu/linux-oracle-6.14*

ubuntu/linux-oracle-6.17<6.17.0-1009.9~24.04.1

6.17.0-1009.9~24.04.1

ubuntu/linux-raspi<6.8.0-1050.54

6.8.0-1050.54

ubuntu/linux-raspi-realtime*

ubuntu/linux-realtime*

ubuntu/linux-riscv*

ubuntu/linux-riscv-6.14*

ubuntu/linux-riscv-6.17<6.17.0-19.19.1~24.04.1

6.17.0-19.19.1~24.04.1

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<6.8.0-2040.41

6.8.0-2040.41

ubuntu/linux-realtime<6.8.1-1045.46

6.8.1-1045.46

ubuntu/linux-realtime-6.14*

ubuntu/linux-realtime-6.17<6.17.0-1008.9~24.04.1

6.17.0-1008.9~24.04.1

ubuntu/linux-aws-fips<6.8.0-1050.53+fips1

6.8.0-1050.53+fips1

ubuntu/linux-azure-fips<6.8.0-1052.58+fips1

6.8.0-1052.58+fips1

ubuntu/linux-fips<6.8.0-106.106+fips1

6.8.0-106.106+fips1

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

6.8.0-1052.55+fips1

ubuntu/linux<6.17.0-19.19

6.17.0-19.19

ubuntu/linux-aws<6.17.0-1009.9

6.17.0-1009.9

ubuntu/linux-azure<6.17.0-1010.10

6.17.0-1010.10

ubuntu/linux-azure-fde*

ubuntu/linux-gcp<6.17.0-1009.9

6.17.0-1009.9

ubuntu/linux-oracle<6.17.0-1009.9

6.17.0-1009.9

ubuntu/linux-raspi<6.17.0-1010.10

6.17.0-1010.10

ubuntu/linux-realtime<6.17.0-1008.9

6.17.0-1008.9

ubuntu/linux-riscv<6.17.0-19.19.1

6.17.0-19.19.1

ubuntu/linux-vmware*

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade debian/linux to a version that resolves this vulnerability.
Fixed in 5.10.251-5Fixed in 6.1.170-3Fixed in 6.1.172-1Fixed in 6.12.86-1Fixed in 6.12.88-1Fixed in 7.0.7-1
Upgrade
Upgrade azurelinux/kernel to a version that resolves this vulnerability.
Fixed in 6.6.130.1-1
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 4.15.0-1200.215~14.04.1
Upgrade
Upgrade ubuntu/linux-aws-hwe to a version that resolves this vulnerability.
Fixed in 4.15.0-1191.204~16.04.1
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 4.15.0-1200.215~16.04.1
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 4.15.0-1184.201~16.04.1
Upgrade
Upgrade ubuntu/linux-hwe to a version that resolves this vulnerability.
Fixed in 4.15.0-249.261~16.04.1
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 4.15.0-1153.164~16.04.1
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 4.15.0-249.261
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 4.15.0-1191.204
Upgrade
Upgrade ubuntu/linux-aws-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1156.166~18.04.1
Upgrade
Upgrade ubuntu/linux-azure-4.15 to a version that resolves this vulnerability.
Fixed in 4.15.0-1200.215
Upgrade
Upgrade ubuntu/linux-azure-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1161.167~18.04.1
Upgrade
Upgrade ubuntu/linux-gcp-4.15 to a version that resolves this vulnerability.
Fixed in 4.15.0-1184.201
Upgrade
Upgrade ubuntu/linux-gcp-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1159.168~18.04.1
Upgrade
Upgrade ubuntu/linux-hwe-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-227.247~18.04.1
Upgrade
Upgrade ubuntu/linux-ibm-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1102.107~18.04.1
Upgrade
Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.
Fixed in 4.15.0-1173.178
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 4.15.0-1153.164
Upgrade
Upgrade ubuntu/linux-oracle-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1154.164~18.04.1
Upgrade
Upgrade ubuntu/linux-raspi-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1139.152~18.04.1
Upgrade
Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.
Fixed in 4.15.0-2129.135
Upgrade
Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.
Fixed in 4.15.0-2109.115
Upgrade
Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.
Fixed in 4.15.0-1146.158
Upgrade
Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.
Fixed in 4.15.0-2092.98
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 5.4.0-227.247
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 5.4.0-1156.166
Upgrade
Upgrade ubuntu/linux-aws-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1103.110~20.04.1
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 5.4.0-1160.166
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-bluefield to a version that resolves this vulnerability.
Fixed in 5.4.0-1116.123
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 5.4.0-1159.168
Upgrade
Upgrade ubuntu/linux-gcp-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1103.112~20.04.1
Upgrade
Upgrade ubuntu/linux-hwe-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-173.183~20.04.1
Upgrade
Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.
Fixed in 5.4.0-1102.107
Upgrade
Upgrade ubuntu/linux-ibm-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1097.100~20.04.1
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Fixed in 5.15.0-1098.104~20.04.1
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Fixed in 5.4.0-1060.63
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Fixed in 5.4.0-1143.152
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Fixed in 5.15.0-173.183~20.04.1
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Fixed in 5.15.0-1055.55~20.04.1
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Fixed in 5.4.0-1154.164
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Fixed in 5.15.0-1100.106~20.04.1
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Fixed in 5.4.0-1139.152
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Fixed in 5.15.0-1098.102~20.04.1
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Fixed in 5.4.0-1074.78
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Fixed in 5.4.0-1156.166+fips1
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Fixed in 5.4.0-1160.166+fips1
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Fixed in 5.4.0-1130.140
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Fixed in 5.4.0-1159.168+fips1
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Fixed in 5.15.0-173.183
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Fixed in 5.15.0-1103.110
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Fixed in 6.8.0-1050.53~22.04.1
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Fixed in 5.15.0-1109.118
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Fixed in 6.8.0-1051.57~22.04.1
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Fixed in 5.15.0-1109.118.1
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Fixed in 6.8.0-1058.65~22.04.1
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Fixed in 5.15.0-1103.112
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Fixed in 6.8.0-1052.55~22.04.1
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Fixed in 5.15.0-1099.105
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Fixed in 5.15.0-1086.94
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Fixed in 6.8.0-106.106~22.04.1
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Fixed in 5.15.0-1097.100
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Fixed in 6.8.0-1049.49~22.04.1
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Fixed in 5.15.0-1098.104
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Fixed in 5.15.0-1095.100
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Fixed in 5.15.0-173.183
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Fixed in 6.8.0-106.106.1~22.04.1
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Fixed in 5.15.0-1098.99
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Fixed in 6.8.0-1049.52~22.04.1
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Fixed in 5.15.0-1055.55
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Fixed in 5.15.0-1044.44
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Fixed in 5.15.0-1100.106
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Fixed in 6.8.0-1047.48~22.04.1
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Fixed in 5.15.0-1097.100
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Fixed in 6.8.0-106.106~22.04.1
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Fixed in 5.15.0-1067.71
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Fixed in 5.15.0-1087.89
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Fixed in 5.15.0-1096.98
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Fixed in 5.15.0-1102.111
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Fixed in 6.8.1-1045.46~22.04.1
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Fixed in 5.15.0-1103.110+fips1
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Fixed in 5.15.0-1109.118+fips1
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Fixed in 5.15.0-173.183+fips1
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Fixed in 5.15.0-1103.112+fips1
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Fixed in 6.8.0-106.106
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Fixed in 6.8.0-1050.53
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Fixed in 6.17.0-1009.9~24.04.2
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Fixed in 6.8.0-1051.57
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Fixed in 6.17.0-1010.10~24.04.1
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Fixed in 6.8.0-1058.65
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Fixed in 6.8.0-1039.42
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Fixed in 6.8.0-1052.55
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Fixed in 6.17.0-1009.9~24.04.3
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Fixed in 6.8.0-1048.53
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Fixed in 6.8.0-1035.38
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Fixed in 6.17.0-19.19~24.04.2
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Fixed in 6.8.0-1049.49
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Fixed in 6.8.0-106.106.1
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Fixed in 6.8.0-1049.52
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Fixed in 6.17.0-1014.14
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Fixed in 6.8.0-1049.52.1
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Fixed in 6.8.0-1020.20
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Fixed in 6.17.0-1017.17
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Fixed in 6.8.0-1047.48
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Fixed in 6.17.0-1009.9~24.04.1
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Fixed in 6.8.0-1050.54
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Fixed in 6.17.0-19.19.1~24.04.1
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Fixed in 6.8.0-1028.29
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Fixed in 6.8.0-1017.21
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Fixed in 6.8.0-2040.41
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Fixed in 6.8.1-1045.46
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Fixed in 6.17.0-1008.9~24.04.1
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Fixed in 6.8.0-1050.53+fips1
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Fixed in 6.8.0-1052.58+fips1
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Fixed in 6.8.0-106.106+fips1
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Fixed in 6.8.0-1052.55+fips1
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Fixed in 6.17.0-19.19
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Fixed in 6.17.0-1009.9
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Fixed in 6.17.0-1010.10
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Fixed in 6.17.0-1009.9
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Fixed in 6.17.0-1009.9
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Fixed in 6.17.0-1010.10
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Fixed in 6.17.0-1008.9
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Fixed in 6.17.0-19.19.1

Event History

Apr 1, 2026

CVE Published

via MITRE·08:36 AM

Data Sourced

via MITRE·08:36 AM

Description

Data Sourced

via OSV·09:16 AM

DescriptionSeverityAffected Software

Data Sourced

via NVD·09:16 AM

RemedyDescriptionSeverityAffected Software

Apr 10, 2026

Data Sourced

via Microsoft·08:02 AM

DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

What is the severity of CVE-2026-23405?

CVE-2026-23405 has been classified with a moderate severity level due to its potential impact on policy namespace limitations.

What systems are affected by CVE-2026-23405?

CVE-2026-23405 affects the Linux kernel specifically in relation to the AppArmor security module.

How do I fix CVE-2026-23405?

To address CVE-2026-23405, ensure that your Linux kernel is updated to the latest version that patches this vulnerability.

What is the nature of CVE-2026-23405?

CVE-2026-23405 is a vulnerability related to the lack of limits on the number of policy namespaces in the AppArmor component of the Linux kernel.

When was CVE-2026-23405 addressed?

CVE-2026-23405 was resolved in recent updates to the Linux kernel, specifically related to AppArmor.

CVE-2026-23405: apparmor: fix: limit the number of levels of policy namespaces

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Affected Software

Remediation

Event History

Frequently Asked Questions

What is the severity of CVE-2026-23405?

What systems are affected by CVE-2026-23405?

How do I fix CVE-2026-23405?

What is the nature of CVE-2026-23405?

When was CVE-2026-23405 addressed?

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