Improper input validation in Linux kernel - CVE-2026-89973
Published: September 16, 2026
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to improper input validation in nvme_tcp_handle_c2h_data() when processing a C2HData PDU for a write command. A remote attacker can send a C2HData PDU in response to a write command to cause a denial of service.
On hosts booted with panic_on_warn, the triggered kernel warning is fatal.
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-2026-89973
linux (Ubuntu package) - addressed in versions 5.15.0-202.212, 7.0.0-42.42
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/0673a2affe45ca76b60de31a83c67b1e60f81bde
- https://git.kernel.org/stable/c/5b115d932f6e769ac80783fb18edd21b0aed256e
- https://git.kernel.org/stable/c/80d56202fbdff8906be6954b2776e5c14a4026f2
- https://git.kernel.org/stable/c/980d990f3c0560d7dfbfbf14699651fdf02f26ee
- https://git.kernel.org/stable/c/a0c389b8a495bda1eb719d2503853c924b7a8355
- https://git.kernel.org/stable/c/b4af7999a998787d5eb6facb5a333e04a4f1d2d9
- https://git.kernel.org/stable/c/df74950ba6008655d4a977d17df7faf4b6e52b74
- https://git.kernel.org/stable/c/f83af377c148f6ad94b41c0e8313f12adf45e1c1
Related Security Bulletins
- Improper input validation in Linux kernel nvme host 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