In the Linux kernel, the following vulnerability has been resolved: net: ipip: require CAPNETADMIN in the device netns for changelink ipipchangelink() operates on at most two netns, devnet(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 CAPNETADMIN only against devnet(dev), so a caller privileged there but not in t->net can rewrite a tunnel that lives in t->net. Gate ipipchangelink() on rtnldevlinknetcapable() at its top, before any attribute is parsed.