CVE-2026-97419

About vulnerability

In the Linux kernel, the following vulnerability has been resolved:

hsr: broadcast netlink notifications in the device’s net namespace

The HSR generic netlink family sets .netnsok = true. HSR devices can live in network namespaces other than init_net.

Two async notifiers broadcast events with genlmsg_multicast(). They are hsr_nl_ringerror() and hsr_nl_nodedown(). That helper delivers only on the default genl socket in init_net. So the events always land in init_net. The network namespace of the device does not matter.

This has two effects. A listener in the device’s own namespace never sees its own ring error and node down events. A privileged listener in init_net receives events from HSR devices in other namespaces. The payload carries the peer node MAC (HSR_A_NODE_ADDR) and the slave port ifindex (HSR_A_IFINDEX).

Switch both callers to genlmsg_multicast_netns(). Other families with .netnsok = true already do this. Examples are gtp, ovpn, team, batman-adv, netdev-genl, ethtool and handshake.

hsr_nl_ringerror() already has the slave port. It uses dev_net(port->dev). hsr_nl_nodedown() takes the namespace from the master port via hsr_port_get_hsr().

Affected product:

AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , Debian 10 ELS , Debian 11 ELS , Oracle Linux 7 ELS , TuxCare 9.6 ESU , TuxCare 9.8 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS

Affected packages:

linux @ 5.4.0 (+13 more)

Live-patch status from KernelCare for each operating system.