NULL pointer dereference in Linux kernel - CVE-2026-74395

Vulnerability identifier: #VU142731

CSH Severity: Low

CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-74395

CWE-ID: CWE-476

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to a null pointer dereference in MLX5_IB_METHOD_DEVX_SUBSCRIBE_EVENT in drivers/infiniband/hw/mlx5/devx.c when handling devx subscribe-event requests and unwinding an error after eventfd acquisition fails. A local user can trigger the error path with a crafted subscribe-event request to cause a denial of service.

The issue occurs because the subscription object is linked into the pending list before fields needed by cleanup are initialized.

Linux kernel
openEuler
kernel
bpftool
bpftool-debuginfo
kernel-debuginfo
kernel-debugsource
kernel-devel
kernel-headers
kernel-source
kernel-tools
kernel-tools-debuginfo
kernel-tools-devel
perf
perf-debuginfo
python3-perf
python3-perf-debuginfo

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel - update to 5.10.0-331.0.0.232
bpftool - update to 5.10.0-331.0.0.232
bpftool-debuginfo - update to 5.10.0-331.0.0.232
kernel-debuginfo - update to 5.10.0-331.0.0.232
kernel-debugsource - update to 5.10.0-331.0.0.232
kernel-devel - update to 5.10.0-331.0.0.232
kernel-headers - update to 5.10.0-331.0.0.232
kernel-source - update to 5.10.0-331.0.0.232
kernel-tools - update to 5.10.0-331.0.0.232
kernel-tools-debuginfo - update to 5.10.0-331.0.0.232
kernel-tools-devel - update to 5.10.0-331.0.0.232
perf - update to 5.10.0-331.0.0.232
perf-debuginfo - update to 5.10.0-331.0.0.232
python3-perf - update to 5.10.0-331.0.0.232
python3-perf-debuginfo - update to 5.10.0-331.0.0.232

• https://git.kernel.org/stable/c/1025dc2f7ba29b04b8687790fa91f9cd1a53141e
• https://git.kernel.org/stable/c/43f8f7946814c8e5f464518246fdbc69b6e32326
• https://git.kernel.org/stable/c/5100febf8e9d6c8c5ba8dc6534c6a5e3376e5989
• https://git.kernel.org/stable/c/6e15b770461eeaa0ff73934922cb670a6a9db04e
• https://git.kernel.org/stable/c/78b9589fda266c71f0f9d0c858d4fa7381a890a5
• https://git.kernel.org/stable/c/7921821fc2b19c01588311f6e7468ae5b68b1f61
• https://git.kernel.org/stable/c/9be9aca28424228586fe9211c373ebdb826ebb6c
• https://git.kernel.org/stable/c/f345e744b6b087188cde2377da5cbe9713b61353

• NULL pointer dereference in Linux kernel hw mlx5 driver
• openEuler 22.03 LTS SP4 update for kernel