NULL pointer dereference in Linux kernel - CVE-2026-43099
Published: May 7, 2026
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to a null pointer dereference in icmp_build_probe() when processing probe requests that use an IPv6 interface identifier while the IPv6 stack is inactive. A remote attacker can send a specially crafted probe request to cause a denial of service.
The issue occurs when IPv6 support is configured as a module and is not loaded.
Affected software
Ubuntu
openEuler
linux (Ubuntu package)
linux-aws (Ubuntu package)
linux-nvidia-tegra (Ubuntu package)
linux-nvidia-tegra-5.15 (Ubuntu package)
linux-ibm-5.15 (Ubuntu package)
linux-azure (Ubuntu package)
linux-azure-5.15 (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-azure-fde (Ubuntu package)
perf-debuginfo
python3-perf-debuginfo
kernel
bpftool
bpftool-debuginfo
kernel-debuginfo
kernel-debugsource
kernel-devel
kernel-headers
kernel-source
kernel-tools
kernel-tools-debuginfo
kernel-tools-devel
perf
python3-perf
kernel-extra-modules
linux-fips (Ubuntu package)
linux-hwe-6.8 (Ubuntu package)
linux-ibm (Ubuntu package)
linux-oracle-6.8 (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-aws-6.8 (Ubuntu package)
linux-azure-fde-6.8 (Ubuntu package)
linux-gcp-fips (Ubuntu package)
How to mitigate CVE-2026-43099
linux (Ubuntu package) - addressed in versions 5.15.0.184.155, 5.15.0-184.194, 5.15.0-184.194~20.04.1, 5.15.0.186.166, 5.15.0-186.196, 5.15.0-186.196~20.04.1, 5.15.0.1075.78, 5.15.0-1075.79, 5.15.0.1095.94, 5.15.0-1095.103, 5.15.0.1104.100, 5.15.0-1104.109, 5.15.0.1108.107, 5.15.0-1108.114, 5.15.0.1111.115, 5.15.0-1111.120+fips1, 5.15.0.1112.102, 5.15.0.1112.109, 5.15.0-1112.122, 5.15.0-1112.122+fips1, 6.8.0-136.136, 6.8.0-1046.50, 6.8.0-1059.67, 6.8.0-1064.72, 6.8.0-1064.72~22.04.1, 6.8.1-1056.57, 6.8.1-1056.57~22.04.2
linux-aws (Ubuntu package) - addressed in versions 5.15.0.186.109, 5.15.0-186.196+fips1, 5.15.0.1106.103, 5.15.0-1106.110, 5.15.0.1107.107, 5.15.0-1107.108, 5.15.0.1112.108, 5.15.0.1112.115, 5.15.0-1112.119, 5.15.0-1112.119+fips1, 5.15.0-1112.119~20.04.1, 6.8.0-1061.64+1
linux-nvidia-tegra (Ubuntu package) - addressed in versions 5.15.0-1053.53, 5.15.0.1053.55, 5.15.0.1064.64, 5.15.0-1064.66
linux-nvidia-tegra-5.15 (Ubuntu package) - update to 5.15.0-1064.66~20.04.1
linux-ibm-5.15 (Ubuntu package) - update to 5.15.0-1106.110~20.04.1
linux-azure (Ubuntu package) - addressed in versions 5.15.0.1109.105, 5.15.0-1109.115, 5.15.0.1117.115, 5.15.0-1117.126, 6.8.0-1063.71, 6.8.0-1063.71~22.04.1
linux-azure-5.15 (Ubuntu package) - addressed in versions 5.15.0-1109.115~20.04.1, 5.15.0-1117.126~20.04.1, 5.15.0-1117.126~20.04.2
linux-azure-fips (Ubuntu package) - addressed in versions 5.15.0.1117.102, 5.15.0-1117.126+fips1, 6.8.0-1063.71+fips2
linux-azure-fde (Ubuntu package) - addressed in versions 5.15.0-1117.126, 6.8.0-1062.69
perf-debuginfo - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
python3-perf-debuginfo - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
kernel - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
bpftool - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
bpftool-debuginfo - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
kernel-debuginfo - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
kernel-debugsource - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
kernel-devel - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
kernel-headers - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
kernel-source - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
kernel-tools - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
kernel-tools-debuginfo - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
kernel-tools-devel - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
perf - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
python3-perf - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
kernel-extra-modules - update to 6.6.0-145.3.14.145
linux-fips (Ubuntu package) - addressed in versions 6.8.0-136.136+fips2, 6.8.0-136.136.2, 6.8.0-136.136.2~22.04.1, 6.8.0-1058.61
linux-hwe-6.8 (Ubuntu package) - update to 6.8.0-136.136~22.04.1
linux-ibm (Ubuntu package) - addressed in versions 6.8.0-1030.31, 6.8.0-1033.34, 6.8.0-1061.62, 6.8.0-1061.62~22.04.1
linux-oracle-6.8 (Ubuntu package) - update to 6.8.0-1058.61~22.04.1
linux-nvidia (Ubuntu package) - addressed in versions 6.8.0-1059.62, 6.8.0-1059.62.1, 6.8.0-1059.62~22.04.1
linux-aws-6.8 (Ubuntu package) - addressed in versions 6.8.0-1061.64+fips1, 6.8.0-1061.64~22.04.1
linux-azure-fde-6.8 (Ubuntu package) - update to 6.8.0-1062.69~22.04.1
linux-gcp-fips (Ubuntu package) - update to 6.8.0-1064.72+fips1
External References
- https://git.kernel.org/stable/c/47a8bf52156ac7e7a581eca31c1f964ba4258d4d
- https://git.kernel.org/stable/c/5b9911582d441f72fe6ccb15ffe3303bbc07f6f5
- https://git.kernel.org/stable/c/6be325206850a0891896d38bcf83a09d8b54ec48
- https://git.kernel.org/stable/c/f91b3ed9e7fa82a70511b5f6901c88379acf2964
- https://git.kernel.org/stable/c/fde29fd9349327acc50d19a0b5f3d5a6c964dfd8
Related Security Bulletins
- NULL pointer dereference in Linux kernel ipv4
- openEuler 24.03 LTS SP3 update for kernel
- Ubuntu update for linux
- Ubuntu update for linux-gcp-fips
- Ubuntu update for linux-nvidia-tegra-5.15
- Ubuntu update for linux
- Ubuntu update for linux-oracle-6.8
- Ubuntu update for linux-fips
- Ubuntu update for linux-ibm-5.15
- Ubuntu update for linux-nvidia-tegra
- Ubuntu update for linux-aws
- Ubuntu update for linux-nvidia
- Ubuntu update for linux-azure-fde
- Ubuntu update for linux-azure
- Ubuntu update for linux-azure-fde-6.8
- Ubuntu update for linux-azure-fips
- Ubuntu update for linux-azure-fde
- Ubuntu update for linux-azure
- Ubuntu update for linux-aws
- openEuler 24.03 LTS SP1 update for kernel
- Ubuntu update for linux-azure-5.15
- Ubuntu update for linux-hwe-6.8
- Ubuntu update for linux-aws-6.8
- Ubuntu update for linux-ibm
- Ubuntu update for linux-azure-fips