net: ipip: require CAP_NET_ADMIN in the device netns for changelink

Summary

In the Linux kernel, the following vulnerability has been resolved: net: ipip: require CAP_NET_ADMIN in the device netns for changelink ipip_changelink() operates on at most two netns, dev_net(dev) and the tunnel link netns t->net. They differ once the device is created in or moved to a netns other than the one the request runs in. The rtnl changelink path checks CAP_NET_ADMIN only against dev_net(dev), so a caller privileged there but not in t->net can rewrite a tunnel that lives in t->net. Gate ipip_changelink() on rtnl_dev_link_net_capable() at its top, before any attribute is parsed.

Timeline

1. Aug 15, 2026, 5:52 AM UTCCVE published
2. Oct 16, 2026, 3:50 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: total

3. Oct 19, 2026, 9:19 PM UTCRecord last updated

Affected versions

• Linux Linux

  From 6c742e714d8c282fd8f8b22d3e20b5141738c1ee · fixed in a7d2642a50282322bc33f34ee7305f2b793df494; From 6c742e714d8c282fd8f8b22d3e20b5141738c1ee · fixed in 068ad9b85f681755f751ebab82ae98146cec163d; From 6c742e714d8c282fd8f8b22d3e20b5141738c1ee · fixed in 91571643e554ae89a91942380d5f5361fb7060a2; From 6c742e714d8c282fd8f8b22d3e20b5141738c1ee · fixed in 983cc4aa7e6f633b34c3ee743771252d7afa9a90; From 6c742e714d8c282fd8f8b22d3e20b5141738c1ee · fixed in 26544021d5c49cc6ae8a968ccb5033e6363854a4; From 6c742e714d8c282fd8f8b22d3e20b5141738c1ee · fixed in 68cadc3698c7de88966d306d12ec9c6217da228a; From 6c742e714d8c282fd8f8b22d3e20b5141738c1ee · fixed in d49edcc65e0a37cc9b386a94415c5d6670ca8b71; From 6c742e714d8c282fd8f8b22d3e20b5141738c1ee · fixed in 8211a26324667980a463c069469a818e71207e02

• Linux Linux

  3.12

• KernelLinux

  From 3.12.0 · fixed in 5.10.266; From 5.11.0 · fixed in 5.15.217; From 5.16.0 · fixed in 6.1.178; From 6.2.0 · fixed in 6.6.145; From 6.7.0 · fixed in 6.12.97; From 6.13.0 · fixed in 6.18.40; From 6.19.0 · fixed in 7.1.5

References 8