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OpenAdvisories
Unscored CVE-2026-31418 EUVD-2026-21941GHSA-vwvf-62c8-j66c

netfilter: ipset: drop logically empty buckets in mtype_del

Published Apr 13, 2026 · Updated Nov 10, 2026 · Assigned by Linux

Vendor: Linux Product: Linux Package: kernel Package: linux Package: linux Package: linux-allwinner-5.19 Package: linux-aws Package: linux-aws-5.0 Package: linux-aws-5.11 Package: linux-aws-5.13 Package: linux-aws-5.15 Package: linux-aws-5.19 Package: linux-aws-5.3 Package: linux-aws-5.4 Package: linux-aws-5.8 Package: linux-aws-6.14 Package: linux-aws-6.17 Package: linux-aws-6.2 Package: linux-aws-6.5 Package: linux-aws-6.8 Package: linux-aws-fips Package: linux-azure Package: linux-azure-5.11 Package: linux-azure-5.13 Package: linux-azure-5.15 Package: linux-azure-5.19 Package: linux-azure-5.3 Package: linux-azure-5.4 Package: linux-azure-5.8 Package: linux-azure-6.11 Package: linux-azure-6.14 Package: linux-azure-6.17 Package: linux-azure-6.2 Package: linux-azure-6.5 Package: linux-azure-6.8 Package: linux-azure-edge Package: linux-azure-fde Package: linux-azure-fde-5.15 Package: linux-azure-fde-5.19 Package: linux-azure-fde-6.14 Package: linux-azure-fde-6.2 Package: linux-azure-fde-6.8 Package: linux-azure-fips Package: linux-azure-nvidia Package: linux-azure-nvidia-6.14 Package: linux-bluefield Package: linux-fips Package: linux-gcp Package: linux-gcp-5.11 Package: linux-gcp-5.13 Package: linux-gcp-5.15 Package: linux-gcp-5.19 Package: linux-gcp-5.3 Package: linux-gcp-5.4 Package: linux-gcp-5.8 Package: linux-gcp-6.11 Package: linux-gcp-6.14 Package: linux-gcp-6.17 Package: linux-gcp-6.2 Package: linux-gcp-6.5 Package: linux-gcp-6.8 Package: linux-gcp-fips Package: linux-gke Package: linux-gke-4.15 Package: linux-gke-5.15 Package: linux-gke-5.4 Package: linux-gkeop Package: linux-gkeop-5.15 Package: linux-gkeop-5.4 Package: linux-hwe Package: linux-hwe-5.11 Package: linux-hwe-5.13 Package: linux-hwe-5.15 Package: linux-hwe-5.19 Package: linux-hwe-5.4 Package: linux-hwe-5.8 Package: linux-hwe-6.11 Package: linux-hwe-6.14 Package: linux-hwe-6.17 Package: linux-hwe-6.2 Package: linux-hwe-6.5 Package: linux-hwe-6.8 Package: linux-hwe-edge Package: linux-ibm Package: linux-ibm-5.15 Package: linux-ibm-5.4 Package: linux-ibm-6.8 Package: linux-intel-5.13 Package: linux-intel-iot-realtime Package: linux-intel-iotg Package: linux-intel-iotg-5.15 Package: linux-iot Package: linux-kvm Package: linux-lowlatency Package: linux-lowlatency-hwe-5.15 Package: linux-lowlatency-hwe-5.19 Package: linux-lowlatency-hwe-6.11 Package: linux-lowlatency-hwe-6.2 Package: linux-lowlatency-hwe-6.5 Package: linux-lowlatency-hwe-6.8 Package: linux-nvidia Package: linux-nvidia-6.11 Package: linux-nvidia-6.17 Package: linux-nvidia-6.2 Package: linux-nvidia-6.5 Package: linux-nvidia-6.8 Package: linux-nvidia-lowlatency Package: linux-nvidia-tegra Package: linux-nvidia-tegra-5.15 Package: linux-nvidia-tegra-igx Package: linux-oem Package: linux-oem-5.10 Package: linux-oem-5.13 Package: linux-oem-5.14 Package: linux-oem-5.17 Package: linux-oem-5.6 Package: linux-oem-6.0 Package: linux-oem-6.1 Package: linux-oem-6.11 Package: linux-oem-6.14 Package: linux-oem-6.17 Package: linux-oem-6.5 Package: linux-oem-6.8 Package: linux-oracle Package: linux-oracle-5.0 Package: linux-oracle-5.11 Package: linux-oracle-5.13 Package: linux-oracle-5.15 Package: linux-oracle-5.3 Package: linux-oracle-5.4 Package: linux-oracle-5.8 Package: linux-oracle-6.14 Package: linux-oracle-6.17 Package: linux-oracle-6.5 Package: linux-oracle-6.8 Package: linux-raspi Package: linux-raspi-5.4 Package: linux-raspi-realtime Package: linux-raspi2 Package: linux-realtime Package: linux-realtime-6.14 Package: linux-realtime-6.17 Package: linux-realtime-6.8 Package: linux-riscv Package: linux-riscv-5.11 Package: linux-riscv-5.15 Package: linux-riscv-5.19 Package: linux-riscv-5.8 Package: linux-riscv-6.14 Package: linux-riscv-6.17 Package: linux-riscv-6.5 Package: linux-riscv-6.8 Package: linux-starfive-5.19 Package: linux-starfive-6.2 Package: linux-starfive-6.5 Package: linux-vmware Package: linux-xilinx Package: linux-xilinx-zynqmp Platform: Linux Ecosystem: Azure Linux Ecosystem: Debian Ecosystem: Ubuntu

Description

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

netfilter: ipset: drop logically empty buckets in mtype_del

mtype_del() counts empty slots below n->pos in k, but it only drops the
bucket when both n->pos and k are zero. This misses buckets whose live
entries have all been removed while n->pos still points past deleted slots.

Treat a bucket as empty when all positions below n->pos are unused and
release it directly instead of shrinking it further.

Affected products

VendorProductAffectedFixed
Linux Linux 5.4.24 – < 5.5, 5.5.8 – < 5.6, 5.6 5.5

Fixed in Linux distributions

Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.

ReleasePackageFixed inAdvisory
Debian 14 linux 6.19.12-1 —
Debian 13 linux 6.12.85-1 —
Debian 12 linux 6.1.170-1 —
ReleasePackageFixed inAdvisory
Ubuntu Nvidia-BlueField 24.04 LTS linux-bluefield 6.8.0-1026.30 —
Ubuntu Nvidia-BlueField 22.04 LTS linux-bluefield 5.15.0-1095.97 —
Ubuntu 26.04 LTS linux-nvidia 7.0.0-1006.6 —
Ubuntu 25.10 linux 6.17.0-40.40 USN-8490-1
Ubuntu 25.10 linux-aws 6.17.0-1019.19 USN-8490-1
Ubuntu 25.10 linux-azure +1 No fix yet —
Ubuntu 25.10 linux-gcp 6.17.0-1020.22 USN-8490-1
Ubuntu 25.10 linux-oracle 6.17.0-1018.18 USN-8490-1
Ubuntu 25.10 linux-raspi 6.17.0-1021.21 USN-8546-1
Ubuntu 25.10 linux-realtime 6.17.0-1017.19 USN-8490-2
Ubuntu 25.10 linux-riscv 6.17.0-40.40.1 —
Ubuntu 24.04 LTS linux 6.8.0-134.134 USN-8492-1
Ubuntu 24.04 LTS linux-aws 6.8.0-1060.63 USN-8492-1
Ubuntu 24.04 LTS linux-aws-6.17 6.17.0-1019.19~24.04.1 USN-8490-1
Ubuntu 24.04 LTS linux-azure 6.8.0-1063.71 USN-8606-1
Ubuntu 24.04 LTS linux-azure-6.17 6.17.0-1021.21~24.04.1 USN-8604-1
Ubuntu 24.04 LTS linux-azure-fde 6.8.0-1062.69 USN-8607-1
Ubuntu 24.04 LTS linux-azure-nvidia 6.8.0-1039.42 —
Ubuntu 24.04 LTS linux-gcp 6.8.0-1063.69 USN-8492-1
Ubuntu 24.04 LTS linux-gcp-6.17 6.17.0-1020.22~24.04.1 USN-8490-1
Ubuntu 24.04 LTS linux-gke 6.8.0-1058.64 USN-8492-2
Ubuntu 24.04 LTS linux-gkeop 6.8.0-1045.48 USN-8492-2
Ubuntu 24.04 LTS linux-hwe-6.17 6.17.0-40.40~24.04.1 USN-8545-1
Ubuntu 24.04 LTS linux-ibm 6.8.0-1060.61 USN-8492-1
Ubuntu 24.04 LTS linux-lowlatency 6.8.0-134.134.1 USN-8497-1
Ubuntu 24.04 LTS linux-nvidia 6.8.0-1058.61 USN-8492-1
Ubuntu 24.04 LTS linux-nvidia-6.17 6.17.0-1026.26 USN-8508-1
Ubuntu 24.04 LTS linux-nvidia-lowlatency 6.8.0-1058.61.1 USN-8492-2
Ubuntu 24.04 LTS linux-nvidia-tegra 6.8.0-1029.30 USN-8498-1
Ubuntu 24.04 LTS linux-oem-6.17 6.17.0-1028.28 USN-8491-1
Ubuntu 24.04 LTS linux-oracle 6.8.0-1057.58 USN-8492-1
Ubuntu 24.04 LTS linux-oracle-6.17 +1 6.17.0-1018.18~24.04.1 USN-8605-1, USN-8490-1
Ubuntu 24.04 LTS linux-raspi 6.8.0-1060.64 USN-8492-4
Ubuntu 24.04 LTS linux-riscv +18 No fix yet —
Ubuntu 24.04 LTS linux-riscv-6.17 6.17.0-38.38.1~24.04.1 —
Ubuntu 24.04 LTS linux-xilinx 6.8.0-1032.33 USN-8499-1
Show 13 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
Ubuntu 22.04 LTS linux 5.15.0-185.195 USN-8493-1
Ubuntu 22.04 LTS linux-aws 5.15.0-1111.118 USN-8493-1
Ubuntu 22.04 LTS linux-aws-6.8 6.8.0-1060.63~22.04.1 USN-8492-2
Ubuntu 22.04 LTS linux-azure +1 5.15.0-1116.125 USN-8493-1
Ubuntu 22.04 LTS linux-azure-6.8 6.8.0-1063.71~22.04.1 USN-8606-1
Ubuntu 22.04 LTS linux-azure-fde-6.8 6.8.0-1062.69~22.04.1 USN-8609-1
Ubuntu 22.04 LTS linux-gcp 5.15.0-1111.121 USN-8493-1
Ubuntu 22.04 LTS linux-gcp-6.8 6.8.0-1063.69~22.04.1 USN-8492-2
Ubuntu 22.04 LTS linux-gke 5.15.0-1107.113 USN-8493-1
Ubuntu 22.04 LTS linux-gkeop 5.15.0-1094.102 USN-8493-1
Ubuntu 22.04 LTS linux-hwe-6.8 6.8.0-136.136~22.04.1 USN-8619-1
Ubuntu 22.04 LTS linux-ibm 5.15.0-1105.109 USN-8493-1
Ubuntu 22.04 LTS linux-ibm-6.8 6.8.0-1060.61~22.04.1 USN-8492-2
Ubuntu 22.04 LTS linux-intel-iotg 5.15.0-1106.112 USN-8493-1
Ubuntu 22.04 LTS linux-kvm 5.15.0-1103.108 USN-8493-1
Ubuntu 22.04 LTS linux-lowlatency 5.15.0-183.193 USN-8493-1
Ubuntu 22.04 LTS linux-lowlatency-hwe-6.8 6.8.0-134.134.1~22.04.1 USN-8497-1
Ubuntu 22.04 LTS linux-nvidia 5.15.0-1106.107 USN-8493-1
Ubuntu 22.04 LTS linux-nvidia-6.8 6.8.0-1058.61~22.04.1 USN-8492-1
Ubuntu 22.04 LTS linux-nvidia-tegra 5.15.0-1063.63 USN-8493-1
Ubuntu 22.04 LTS linux-nvidia-tegra-igx 5.15.0-1052.52 USN-8493-1
Ubuntu 22.04 LTS linux-oracle 5.15.0-1108.114 USN-8493-1
Ubuntu 22.04 LTS linux-oracle-6.8 6.8.0-1057.58~22.04.1 USN-8492-2
Ubuntu 22.04 LTS linux-raspi 5.15.0-1105.108 USN-8527-1
Ubuntu 22.04 LTS linux-riscv +32 No fix yet —
Ubuntu 22.04 LTS linux-riscv-6.8 6.8.0-134.134~22.04.1 —
Ubuntu 22.04 LTS linux-xilinx-zynqmp 5.15.0-1074.78 USN-8528-1
Ubuntu 20.04 LTS linux-gke +28 No fix yet —
Ubuntu 18.04 LTS linux-gcp +14 No fix yet —
Ubuntu 16.04 LTS linux-hwe-edge No fix yet —
Ubuntu Pro Realtime 24.04 LTS linux-raspi-realtime 6.8.0-2049.50 USN-8492-3
Ubuntu Pro Realtime 24.04 LTS linux-realtime 6.8.1-1055.56 USN-8492-1
Ubuntu Pro Realtime 24.04 LTS linux-realtime-6.14 No fix yet —
Ubuntu Pro Realtime 24.04 LTS linux-realtime-6.17 6.17.0-1017.19~24.04.1 USN-8490-2
Ubuntu Pro Realtime 22.04 LTS linux-intel-iot-realtime 5.15.0-1103.105 USN-8493-1
Ubuntu Pro Realtime 22.04 LTS linux-realtime 5.15.0-1110.119 USN-8493-1
Ubuntu Pro Realtime 22.04 LTS linux-realtime-6.8 6.8.1-1055.56~22.04.1 USN-8492-1
Ubuntu Pro FIPS 20.04 LTS linux-fips +3 No fix yet —
Ubuntu Pro FIPS-updates 24.04 LTS linux-aws-fips 6.8.0-1060.63+fips1 USN-8492-1
Ubuntu Pro FIPS-updates 24.04 LTS linux-azure-fips 6.8.0-1062.69+fips1 USN-8492-5
Ubuntu Pro FIPS-updates 24.04 LTS linux-fips 6.8.0-134.134+fips1 USN-8492-5
Ubuntu Pro FIPS-updates 24.04 LTS linux-gcp-fips 6.8.0-1063.69+fips1 USN-8492-1
Ubuntu Pro FIPS-updates 22.04 LTS linux-aws-fips 5.15.0-1111.118+fips1 USN-8493-1
Ubuntu Pro FIPS-updates 22.04 LTS linux-azure-fips 5.15.0-1116.125+fips1 USN-8547-2
Ubuntu Pro FIPS-updates 22.04 LTS linux-fips 5.15.0-185.195+fips1 USN-8493-1
Ubuntu Pro FIPS-updates 22.04 LTS linux-gcp-fips 5.15.0-1111.121+fips1 USN-8493-1
Ubuntu Pro FIPS-updates 20.04 LTS linux-aws-fips 5.4.0-1161.172+fips1 USN-8615-1
Ubuntu Pro FIPS-updates 20.04 LTS linux-azure-fips 5.4.0-1166.172+fips1 USN-8615-1
Ubuntu Pro FIPS-updates 20.04 LTS linux-fips 5.4.0-1135.145 USN-8615-1
Ubuntu Pro FIPS-updates 20.04 LTS linux-gcp-fips 5.4.0-1164.173+fips1 USN-8615-1
Ubuntu Pro FIPS-preview 22.04 LTS linux-fips +3 No fix yet —
Ubuntu Pro 20.04 LTS linux 5.4.0-233.253 USN-8615-1
Ubuntu Pro 20.04 LTS linux-aws 5.4.0-1161.172 USN-8615-1
Ubuntu Pro 20.04 LTS linux-aws-5.15 5.15.0-1111.118~20.04.1 USN-8493-1
Ubuntu Pro 20.04 LTS linux-azure 5.4.0-1166.172 USN-8615-1
Ubuntu Pro 20.04 LTS linux-azure-5.15 +1 5.15.0-1116.125~20.04.1 USN-8493-1
Ubuntu Pro 20.04 LTS linux-bluefield 5.4.0-1120.127 USN-8615-1
Ubuntu Pro 20.04 LTS linux-gcp 5.4.0-1164.173 USN-8615-1
Ubuntu Pro 20.04 LTS linux-gcp-5.15 5.15.0-1111.121~20.04.1 USN-8547-1
Ubuntu Pro 20.04 LTS linux-hwe-5.15 5.15.0-185.195~20.04.1 USN-8493-1
Ubuntu Pro 20.04 LTS linux-ibm 5.4.0-1107.112 USN-8616-1
Ubuntu Pro 20.04 LTS linux-ibm-5.15 +1 5.15.0-1105.109~20.04.1 USN-8493-1
Ubuntu Pro 20.04 LTS linux-intel-iotg-5.15 5.15.0-1106.112~20.04.1 USN-8547-1
Ubuntu Pro 20.04 LTS linux-iot 5.4.0-1065.68 USN-8615-1
Ubuntu Pro 20.04 LTS linux-kvm 5.4.0-1148.157 USN-8617-1
Ubuntu Pro 20.04 LTS linux-lowlatency-hwe-5.15 5.15.0-183.193~20.04.1 USN-8493-1
Ubuntu Pro 20.04 LTS linux-nvidia-tegra-5.15 5.15.0-1063.63~20.04.1 USN-8493-1
Ubuntu Pro 20.04 LTS linux-oracle 5.4.0-1159.169 USN-8615-1
Ubuntu Pro 20.04 LTS linux-oracle-5.15 5.15.0-1108.114~20.04.1 USN-8493-2
Ubuntu Pro 20.04 LTS linux-raspi 5.4.0-1144.157 USN-8615-2
Ubuntu Pro 20.04 LTS linux-xilinx-zynqmp 5.4.0-1079.83 USN-8615-1
Ubuntu Pro 18.04 LTS linux-aws-5.4 5.4.0-1161.172~18.04.1 USN-8615-1
Ubuntu Pro 18.04 LTS linux-azure-5.4 5.4.0-1166.172~18.04.1 USN-8615-1
Ubuntu Pro 18.04 LTS linux-gcp-5.4 5.4.0-1164.173~18.04.1 USN-8615-1
Ubuntu Pro 18.04 LTS linux-hwe-5.4 5.4.0-233.253~18.04.1 USN-8615-1
Ubuntu Pro 18.04 LTS linux-ibm-5.4 5.4.0-1107.112~18.04.1 USN-8616-1
Ubuntu Pro 18.04 LTS linux-oracle-5.4 5.4.0-1159.169~18.04.1 USN-8615-1
Ubuntu Pro 18.04 LTS linux-raspi-5.4 5.4.0-1144.157~18.04.1 USN-8615-2
ReleasePackageFixed inAdvisory
SLES 15 SP7 kernel-64kb +7 6.4.0-150700.53.81.1 SUSE-SU-2026:4254-1
SLES 15 SP7 kernel-default-base 6.4.0-150700.53.81.1.150700.17.45.1 SUSE-SU-2026:4254-1
Show 7 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
SLES for SAP 16.0 kernel-64kb +8 6.12.0-160000.38.1 SUSE-SU-2026:23902-1
SLES for SAP 16.0 kernel-default-base 6.12.0-160000.38.1.160000.2.23 SUSE-SU-2026:23902-1
SLES 16.0 kernel-64kb +8 6.12.0-160000.38.1 SUSE-SU-2026:23902-1, SUSE-SU-2026:23897-1
SLES 16.0 kernel-default-base 6.12.0-160000.38.1.160000.2.23 SUSE-SU-2026:23902-1
SLE Micro 6.2 kernel-default-base 6.12.0-160000.38.1.160000.2.23 SUSE-SU-2026:23887-1
SLE Micro 6.2 kernel-rt +5 6.12.0-160000.38.1 SUSE-SU-2026:23887-1, SUSE-SU-2026:23881-1
SLE Micro 6.1 kernel-default-base 6.4.0-52.1.21.34 SUSE-SU-2026:23529-1
SLE Micro 6.1 kernel-rt +4 6.4.0-52.1 SUSE-SU-2026:23529-1, SUSE-SU-2026:23528-1
SLE Micro 6.0 kernel-default-base 6.4.0-52.1.21.36 SUSE-SU-2026:23481-1
SLE Micro 6.0 kernel-rt +4 6.4.0-52.1 SUSE-SU-2026:23481-1, SUSE-SU-2026:23477-1
SLE Live Patching 15 SP7 kernel-default 6.4.0-150700.53.81.1 SUSE-SU-2026:4254-1
SLE Live Patching 15 SP7 kernel-livepatch-SLE15-SP7-RT_Update_20 1-150700.1.3.1 SUSE-SU-2026:4120-1
SLE Live Patching 15 SP7 kernel-livepatch-SLE15-SP7_Update_21 1-150700.15.3.1 SUSE-SU-2026:4254-1
SUSE Real Time Module 15 SP7 kernel-rt +2 6.4.0-150700.7.75.1 SUSE-SU-2026:4120-1
ReleasePackageFixed inAdvisory
openSUSE Leap 16.0 kernel-default-base 6.12.0-160000.38.1.160000.2.22 openSUSE-SU-2026:21910-1
openSUSE Leap 16.0 kernel-rt +11 6.12.0-160000.38.1 openSUSE-SU-2026:21910-1

Amazon Linux

ReleasePackageFixed inAdvisory
Amazon Linux 2023 kernel-livepatch-6.18.25-55.108 +2 1:1.0-0.amzn2023 ALAS2023-2026-1695, ALAS2023-2026-1693, ALAS2023-2026-1681
Amazon Linux 2023 perf +14 1:6.1.168-202.320.amzn2023 ALAS2023-2026-1681
Amazon Linux 2023 perf6.12 +11 1:6.12.83-113.160.amzn2023 ALAS2023-2026-1695
Amazon Linux 2023 perf6.18 +11 1:6.18.25-55.108.amzn2023 ALAS2023-2026-1693

Azure Linux

ReleasePackageFixed inAdvisory
Azure Linux 3 kernel 6.6.134.1-2 —

Oracle Linux

ReleasePackageFixed inAdvisory
Oracle Linux 9 kernel-uek +34 6.12.0-204.92.4.2.el10uek ELSA-2026-50372

Advisories 50

References