CVE-2026-63914

HIGH
MEDIUM Priority: 0.01 BB Relevance: 40/100
Published: 2026-07-19 Modified: 2026-10-30 First seen: 2026-10-30 Status: active

Attack Surface

Low Complexity No Interaction Conf. Impact Scope Change

CVSS Vector Breakdown

AV: Local
AC: Low
PR: Low
UI: None
S: Changed
C: High
I: None
A: Low

Description

In the Linux kernel, the following vulnerability has been resolved: xfrm: route MIGRATE notifications to caller's 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_net's 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 caller's 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 Classification (2)

Affected Software (6)

VendorProductVersion
linux linux_kernel 2.6.21 – 5.10.259
linux linux_kernel 7.1
linux linux_kernel 7.1
linux linux_kernel 7.1
linux linux_kernel 7.1
linux linux_kernel 7.1

Bug Bounty Relevance

40 / 100
✓ Low complexity
✓ No user interaction

CVSS Score

7.3 / 10.0 v3.1
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:L

EPSS — Exploitation Probability

0.15%
Raw Score 0.001470
Percentile 3.9%
Date 2026-10-30

Intelligence Sources

nvd ref →