Race condition in Linux kernel - CVE-2026-74662

Vulnerability identifier: #VU144857

CSH Severity: Medium

CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-74662

CWE-ID: CWE-362

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to a race condition in inet_frag_create() and the fragment queue timer handling in net/ipv4/inet_fragment.c when processing fragmented packets with a zero or negative fragment timeout. A remote attacker can send specially crafted fragmented network traffic to cause a denial of service.

The issue occurs because the timer may run before the queue is published in the fqdir rhashtable, which can leave a stale hash node after reference handling becomes unbalanced.

Linux kernel
Debian Linux
openEuler
Ubuntu
kernel
python3-perf-debuginfo
python3-perf
python2-perf-debuginfo
python2-perf
perf-debuginfo
perf
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-source
kernel-devel
kernel-debugsource
kernel-debuginfo
bpftool-debuginfo
bpftool
linux-nvidia-tegra (Ubuntu package)
linux (Debian package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel - update to 4.19.90-2609.3.0.0391
python3-perf-debuginfo - update to 4.19.90-2609.3.0.0391
python3-perf - update to 4.19.90-2609.3.0.0391
python2-perf-debuginfo - update to 4.19.90-2609.3.0.0391
python2-perf - update to 4.19.90-2609.3.0.0391
perf-debuginfo - update to 4.19.90-2609.3.0.0391
perf - update to 4.19.90-2609.3.0.0391
kernel-tools-devel - update to 4.19.90-2609.3.0.0391
kernel-tools-debuginfo - update to 4.19.90-2609.3.0.0391
kernel-tools - update to 4.19.90-2609.3.0.0391
kernel-source - update to 4.19.90-2609.3.0.0391
kernel-devel - update to 4.19.90-2609.3.0.0391
kernel-debugsource - update to 4.19.90-2609.3.0.0391
kernel-debuginfo - update to 4.19.90-2609.3.0.0391
bpftool-debuginfo - update to 4.19.90-2609.3.0.0391
bpftool - update to 4.19.90-2609.3.0.0391
linux-nvidia-tegra (Ubuntu package) - update to 6.8.0-1036.39+1
linux (Debian package) - update to 6.12.107-1

• https://git.kernel.org/stable/c/653d7ddf6cba867777a3d14c4f83ace008c5ad13
• https://git.kernel.org/stable/c/928128865e43b197e30688dc1bc991592c97edcf
• https://git.kernel.org/stable/c/9f904dd3e455750e5d4ec9b2f134835811b85a2f

• Race condition in Linux kernel ipv4
• Debian update for linux
• openEuler 20.03 LTS SP4 update for kernel
• Ubuntu update for linux-nvidia-tegra