CVE-2026-63914

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

xfrm: route MIGRATE notifications to callers netns

xfrm_send_migrate() in net/xfrm/xfrm_user.c and pfkey_send_migrate() in net/key/af_key.c both hardcode &init_net for the multicast that announces a successful XFRM_MSG_MIGRATE / SADB_X_MIGRATE.

XFRM_MSG_MIGRATE arrives on a per-netns NETLINK_XFRM socket, and the rest of the xfrm/af_key netlink path was made netns-aware in 2008. The other 14 multicast paths in xfrm_user.c route their event using xs_net(x), xp_net(xp) or sock_net(skb->sk); only the migrate path was missed.

Two consequences of the init_net hardcoding:

1. The notification (selector, old/new endpoint addresses, and the km_address) is delivered to listeners on init_nets XFRMNLGRP_MIGRATE / pfkey BROADCAST_ALL groups rather than on the issuing netns. An IKE daemon running in init_net therefore receives migration notifications originating from any other netns on the host.

2. An IKE daemon running inside a non-init netns and subscribed to its own XFRMNLGRP_MIGRATE / pfkey groups never receives the notification of its own migration. IKEv2 MOBIKE / address-update handling inside a netns is silently broken.

Thread struct net through km_migrate() and the xfrm_mgr.migrate function pointer, drop the &init_net override in xfrm_send_migrate() and pfkey_send_migrate(), and pass the callers net (already in scope in xfrm_migrate() via sock_net(skb->sk)) all the way down. struct xfrm_mgr is in-tree only and not exported as a stable API, so the function-pointer signature change is internal.

pfkey_broadcast() is already netns-aware via net_generic(net, pfkey_net_id) since the pernet conversion. The five other pfkey_broadcast() callers in af_key.c already pass xs_net(x), sock_net(sk) or a per-netns net, so this only removes the &init_net outlier.

Weakness

The product exposes a resource to the wrong control sphere, providing unintended actors with inappropriate access to the resource.

Affected Software

Extended Description

Resources such as files and directories may be inadvertently exposed through mechanisms such as insecure permissions, or when a program accidentally operates on the wrong object. For example, a program may intend that private files can only be provided to a specific user. This effectively defines a control sphere that is intended to prevent attackers from accessing these private files. If the file permissions are insecure, then parties other than the user will be able to access those files. A separate control sphere might effectively require that the user can only access the private files, but not any other files on the system. If the program does not ensure that the user is only requesting private files, then the user might be able to access other files on the system. In either case, the end result is that a resource has been exposed to the wrong party.

References

• https://git.kernel.org/stable/c/00f2c451e57df50b1151d9b2254878f106b7c892
• https://git.kernel.org/stable/c/26ce8dbf2e23fe4fcc3351d19ef6d3fb703ed126
• https://git.kernel.org/stable/c/448bb92ca101dde8a6e88b4dc824044b4e341604
• https://git.kernel.org/stable/c/6df8157547347b5257bf640a0ae3dfc4411e06cd
• https://git.kernel.org/stable/c/7e2a4f7ca0952820731ef7bdadfc9a9e9d3571b4
• https://git.kernel.org/stable/c/a306cf2ac8849c487791369fad6f216399d000f6
• https://git.kernel.org/stable/c/bafc7d0774b9bf52909c70ed990bc5ccf7ec4bad
• https://git.kernel.org/stable/c/fe463798343382c8fe9416a95959f005a3c30aa5