Improper access control in Linux kernel - CVE-2026-31692

Vulnerability identifier: #VU128648

CSH Severity: Low

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

CVE-ID: CVE-2026-31692

CWE-ID: CWE-284

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to create interfaces in arbitrary network namespaces.

The vulnerability exists due to improper access control in rtnl_newlink() when creating paired devices with a peer network namespace. A local user can create veth, vxcan, or netkit interfaces to create interfaces in arbitrary network namespaces.

Exploitation requires a user namespace.

Linux kernel
Red Hat Enterprise Linux for Real Time
Red Hat Enterprise Linux for Real Time for NFV
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for ARM 64
Red Hat CodeReady Linux Builder for x86_64
Red Hat CodeReady Linux Builder for Power, little endian
Red Hat CodeReady Linux Builder for ARM 64
kernel (Red Hat package)
kernel-rt (Red Hat package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel (Red Hat package) - update to 4.18.0-553.150.1.el8_10
kernel-rt (Red Hat package) - update to 4.18.0-553.150.1.rt7.491.el8_10

• https://git.kernel.org/stable/c/0975b64ffb34560042090a5986c3a02e6c80f36f
• https://git.kernel.org/stable/c/7b735ef81286007794a227ce2539419479c02a5f
• https://git.kernel.org/stable/c/d04cc16d3624218a5458b2b664ae431f1b3b334d

• Improper access control in Linux kernel core
• Red Hat Enterprise Linux 8 update for kernel-rt
• Red Hat Enterprise Linux 8 update for kernel