Out-of-bounds write in Linux kernel - CVE-2026-89965
Published: September 16, 2026
Vulnerability details
The vulnerability allows a local user to execute arbitrary code.
The vulnerability exists due to an out-of-bounds write in the nvdimm/btt arena I/O path when processing a crafted or foreign arena whose nfree value is below the lane count. A local user can provide a crafted or foreign arena to write past per-lane freelist and rtt array allocations and execute arbitrary code.
Affected software
Debian Linux
Ubuntu
openEuler
linux (Ubuntu package)
linux-kvm (Ubuntu package)
linux-aws (Ubuntu package)
linux-gcp (Ubuntu package)
linux-azure (Ubuntu package)
linux-oracle (Ubuntu package)
linux-lowlatency (Ubuntu package)
linux-gke (Ubuntu package)
linux-aws-5.15 (Ubuntu package)
linux-lowlatency-hwe-5.15 (Ubuntu package)
linux-hwe-5.15 (Ubuntu package)
linux-fips (Ubuntu package)
linux-azure-5.15 (Ubuntu package)
linux-gkeop (Ubuntu package)
linux-azure-fde-5.15 (Ubuntu package)
linux-ibm-5.15 (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-intel-iotg (Ubuntu package)
linux-nvidia-tegra-igx (Ubuntu package)
linux-nvidia-tegra (Ubuntu package)
linux-realtime (Ubuntu package)
linux-ibm (Ubuntu package)
linux-intel-iotg-5.15 (Ubuntu package)
linux-oracle-5.15 (Ubuntu package)
linux-gcp-5.15 (Ubuntu package)
linux-nvidia-tegra-5.15 (Ubuntu package)
linux-azure-fde (Ubuntu package)
linux-intel-iot-realtime (Ubuntu package)
linux-gcp-fips (Ubuntu package)
linux-aws-fips (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-hwe-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
kernel
python3-perf-debuginfo
python3-perf
perf-debuginfo
perf
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-source
kernel-headers
kernel-devel
kernel-debugsource
kernel-debuginfo
bpftool-debuginfo
bpftool
linux (Debian package)
How to mitigate CVE-2026-89965
linux-kvm (Ubuntu package) - update to 5.15.0-1111.116
linux-aws (Ubuntu package) - addressed in versions 5.15.0-1119.126, 7.0.0-1016.17
linux-gcp (Ubuntu package) - addressed in versions 5.15.0-1120.130, 7.0.0-1016.18
linux-azure (Ubuntu package) - update to 5.15.0-1125.134
linux-oracle (Ubuntu package) - addressed in versions 5.15.0-1116.122, 7.0.0-1015.16
linux-lowlatency (Ubuntu package) - update to 5.15.0-197.207
linux-gke (Ubuntu package) - update to 5.15.0-1115.121
linux-aws-5.15 (Ubuntu package) - update to 5.15.0-1119.126~20.04.1
linux-lowlatency-hwe-5.15 (Ubuntu package) - update to 5.15.0-197.207~20.04.1
linux-hwe-5.15 (Ubuntu package) - update to 5.15.0-202.212~20.04.1
linux-fips (Ubuntu package) - update to 5.15.0-202.212+fips1
linux-azure-5.15 (Ubuntu package) - update to 5.15.0-1125.134~20.04.1
linux-gkeop (Ubuntu package) - update to 5.15.0-1102.110
linux-azure-fde-5.15 (Ubuntu package) - update to 5.15.0-1124.133~20.04.1
linux-ibm-5.15 (Ubuntu package) - update to 5.15.0-1113.117~20.04.1
linux-nvidia (Ubuntu package) - update to 5.15.0-1114.115
linux-intel-iotg (Ubuntu package) - update to 5.15.0-1114.120
linux-nvidia-tegra-igx (Ubuntu package) - update to 5.15.0-1059.59
linux-nvidia-tegra (Ubuntu package) - addressed in versions 5.15.0-1070.72, 6.8.0-1038.42
linux-realtime (Ubuntu package) - update to 5.15.0-1118.127
linux-ibm (Ubuntu package) - addressed in versions 5.15.0-1113.117, 7.0.0-1017.17
linux-intel-iotg-5.15 (Ubuntu package) - update to 5.15.0-1114.120~20.04.1
linux-oracle-5.15 (Ubuntu package) - update to 5.15.0-1116.122~20.04.1
linux-gcp-5.15 (Ubuntu package) - update to 5.15.0-1120.130~20.04.1
linux-nvidia-tegra-5.15 (Ubuntu package) - update to 5.15.0-1070.72~20.04.1
linux-azure-fde (Ubuntu package) - update to 5.15.0-1124.133
linux-intel-iot-realtime (Ubuntu package) - update to 5.15.0-1111.115
linux-gcp-fips (Ubuntu package) - update to 5.15.0-1120.130+fips1
linux-aws-fips (Ubuntu package) - update to 5.15.0-1119.126+fips1
linux-azure-fips (Ubuntu package) - update to 5.15.0-1125.134+fips1
linux-hwe-7.0 (Ubuntu package) - update to 7.0.0-42.42~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1017.17
kernel - update to 5.10.0-337.0.0.238
python3-perf-debuginfo - update to 5.10.0-337.0.0.238
python3-perf - update to 5.10.0-337.0.0.238
perf-debuginfo - update to 5.10.0-337.0.0.238
perf - update to 5.10.0-337.0.0.238
kernel-tools-devel - update to 5.10.0-337.0.0.238
kernel-tools-debuginfo - update to 5.10.0-337.0.0.238
kernel-tools - update to 5.10.0-337.0.0.238
kernel-source - update to 5.10.0-337.0.0.238
kernel-headers - update to 5.10.0-337.0.0.238
kernel-devel - update to 5.10.0-337.0.0.238
kernel-debugsource - update to 5.10.0-337.0.0.238
kernel-debuginfo - update to 5.10.0-337.0.0.238
bpftool-debuginfo - update to 5.10.0-337.0.0.238
bpftool - update to 5.10.0-337.0.0.238
linux (Debian package) - update to 6.12.111-1
External References
- https://git.kernel.org/stable/c/59d5cd1f42b4bab3609512c3cb3d3540d3d21da7
- https://git.kernel.org/stable/c/6a1f2e5ed9267ca19187038ac635393c165213ac
- https://git.kernel.org/stable/c/6b1faf1f099f7060b5f1f2f0d024132581f1726e
- https://git.kernel.org/stable/c/6f79d1a5f2611a3d36e9312be5425cd9cb397c51
- https://git.kernel.org/stable/c/9dfa11cef4750b67591307f2c62e47a23d60e4b7
- https://git.kernel.org/stable/c/eb491343d2d1784121ad9af91c25b338c28913c3
- https://git.kernel.org/stable/c/f6c5313aae794ecca8f762c1a3493de5c266f120
- https://git.kernel.org/stable/c/f9bf05c63b77d000e9c01f3e47af36973887d350
Related Security Bulletins
- Out-of-bounds write in Linux kernel nvdimm driver
- Debian update for linux
- openEuler 22.03 LTS SP4 update for kernel
- Ubuntu update for linux-azure-fde
- Ubuntu update for linux-oem-7.0
- Ubuntu update for linux, linux-aws, linux-gcp and more
- Ubuntu update for linux-nvidia-tegra, linux-nvidia-tegra-5.15, linux-nvidia-tegra-igx
- Ubuntu update for linux, linux-aws, linux-aws-5.15 and more
- Ubuntu update for linux-nvidia-tegra