CVE-2026-31692: linux kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: rtnetlink: add missing netlink_ns_capable() check for peer netns rtnl_newlink() lacks a CAP_NET_ADMIN capability check on the peer network namespace when creating paired devices (veth, vxcan, netkit). This allows an unprivileged user with a user namespace to create interfaces in arbitrary network namespaces, including init_net. Add a netlink_ns_capable() check for CAP_NET_ADMIN in the peer namespace before allowing device creation to proceed.
CVE-2026-31692CVSS 5.5Linux

CVE-2026-31692: linux kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: rtnetlink: add missing netlink_ns_capable() check for peer netns rtnl_newlink() lacks a CAP_NET_ADMIN capability check on the peer network namespace when creating paired devices (veth, vxcan, netkit). This allows an unprivileged user with a user namespace to create interfaces in arbitrary network namespaces, including init_net. Add a netlink_ns_capable() check for CAP_NET_ADMIN in the peer namespace before allowing device creation to proceed.

CVSS
5.5 MEDIUM
EPSS
2.1%
Known exploited
not in KEV
Product
linux kernel

What is known

In the Linux kernel, the following vulnerability has been resolved: rtnetlink: add missing netlink_ns_capable() check for peer netns rtnl_newlink() lacks a CAP_NET_ADMIN capability check on the peer network namespace when creating paired devices (veth, vxcan, netkit). This allows an unprivileged user with a user namespace to create interfaces in arbitrary network namespaces, including init_net. Add a netlink_ns_capable() check for CAP_NET_ADMIN in the peer namespace before allowing device creation to proceed.

Sources

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