CVE-2026-63921

CVE-2026-63921 affects the Linux kernel’s IPv6 VTI (ip6: vti) implementation. The root cause is a collision-lookup using dev_net(dev) in vti6_siocdevprivate(), which, after tunnels migrate between namespaces, can cause SIOCCHGTUNNEL to resolve against the wrong netns. This enables a scenario wher...