Use-after-free in Linux kernel - CVE-2026-74520

Vulnerability identifier: #VU143255

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-2026-74520

CWE-ID: CWE-416

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 use-after-free in the IOMMUFD IOPF group handling logic when processing page fault groups during device detach or HWPT replacement. A local user can trigger fault handling and later access a freed group to cause a denial of service.

The issue occurs because an accepted group can remain referenced by the IOMMUFD deliver list or response xarray after being freed through the generic pending list.

Linux kernel
openEuler
kernel
bpftool
bpftool-debuginfo
kernel-debuginfo
kernel-debugsource
kernel-devel
kernel-extra-modules
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 6.6.0-145.3.31.162
bpftool - update to 6.6.0-145.3.31.162
bpftool-debuginfo - update to 6.6.0-145.3.31.162
kernel-debuginfo - update to 6.6.0-145.3.31.162
kernel-debugsource - update to 6.6.0-145.3.31.162
kernel-devel - update to 6.6.0-145.3.31.162
kernel-extra-modules - update to 6.6.0-145.3.31.162
kernel-headers - update to 6.6.0-145.3.31.162
kernel-source - update to 6.6.0-145.3.31.162
kernel-tools - update to 6.6.0-145.3.31.162
kernel-tools-debuginfo - update to 6.6.0-145.3.31.162
kernel-tools-devel - update to 6.6.0-145.3.31.162
perf - update to 6.6.0-145.3.31.162
perf-debuginfo - update to 6.6.0-145.3.31.162
python3-perf - update to 6.6.0-145.3.31.162
python3-perf-debuginfo - update to 6.6.0-145.3.31.162

• https://git.kernel.org/stable/c/4e74a369236424114b94cf6a9f5ff9e848b430b4
• https://git.kernel.org/stable/c/6da8f37419dd4c456f26fc203f04e000186f4b3d
• https://git.kernel.org/stable/c/738e6f32e61d80b554e37015ecb7bc620b88001c

• Use-after-free in Linux kernel IOMMUFD IOPF group handling logic
• openEuler 24.03 LTS SP3 update for kernel