{"id":"AZL-88887","summary":"CVE-2026-46120 affecting package kernel for versions less than 6.6.141.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nip6_gre: Use cached t-\u003enet in ip6erspan_changelink().\n\nAfter commit 5e72ce3e3980 (\"net: ipv6: Use link netns in newlink() of\nrtnl_link_ops\"), ip6erspan_newlink() correctly resolves the per-netns\nip6gre hash via link_net. ip6erspan_changelink() was not converted in\nthat series and still uses dev_net(dev), which diverges from the\ndevice's creation netns after IFLA_NET_NS_FD migration.\n\nThis re-inserts the tunnel into the wrong per-netns hash. The\noriginal netns keeps a stale entry. When that netns is later\ndestroyed, ip6gre_exit_rtnl_net() walks the stale entry, producing a\nslab-use-after-free reported by KASAN, followed by a kernel BUG at\nnet/core/dev.c (LIST_POISON1) in unregister_netdevice_many_notify().\n\nReachable from an unprivileged user namespace (unshare --user\n--map-root-user --net).\n\nip6gre_changelink() earlier in the same file already uses the cached\nt-\u003enet; only ip6erspan_changelink() has the wrong shape.","modified":"2026-08-28T17:48:09.780686618Z","published":"2026-05-28T10:16:27Z","upstream":["CVE-2026-46120"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-46120"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.141.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-88887.json"}}],"schema_version":"1.9.0"}