{"id":"CVE-2026-63917","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-63917","generatedAt":"2026-10-28T00:28:57.535Z","title":"In the Linux kernel, the following vulnerability has been resolved: ip6: vti: Use ip6_tnl.net in vti6_changelink(). ip netns add ns1 ip netns add ns2 ip -n ns1 link add vti6_test type vti6 remote ::1 local ::2 key 7 ip -n ns1 link set vti6_test netns…","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nip6: vti: Use ip6_tnl.net in vti6_changelink().\n\nip netns add ns1\nip netns add ns2\nip -n ns1 link add vti6_test type vti6 remote ::1 local ::2 key 7\nip -n ns1 link set vti6_test netns ns2\nip -n ns2 link set vti6_test type vti6 remote ::3 local ::4 key 9\nip netns del ns2\nip netns del ns1\n[  132.495484] ------------[ cut here ]------------\n[  132.497609] kernel BUG at net/core/dev.c:12376!\n\nCommit 61220ab34948 (\"vti6: Enable namespace changing\") dropped\nNETIF_F_NETNS_LOCAL from vti6 devices. A vti6 tunnel can then\nmove through IFLA_NET_NS_FD. After the move dev_net(dev) points\nat the new netns while t->net stays at the creation netns.\n\nvti6_changelink() and vti6_update() still use dev_net(dev) and\ndev_net(t->dev). They unlink from one per netns hash and relink\ninto another. The creation netns is left with a stale entry.\ncleanup_net() of that netns later walks freed memory.\n\nReachable from an unprivileged user namespace (unshare --user\n--map-root-user --net). Cross tenant scope on container hosts.","published":"2026-07-19T16:17:10.000Z","lastModified":"2026-10-19T21:17:11.000Z","status":"Awaiting Analysis","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":{"version":"3.1","score":8.8,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H"},"cwe":["CWE-416"],"affected":[],"epss":{"score":0.00169,"percentile":0.06259,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.17%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/0cdce7618464f7fb06f461e8f4ad575cb1d570f4","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/11b326fb0a374f4654f9be22d0f0f7abd9f7d3fe","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/225b467e3b631f38be22e4b38062a1fed02fdd21","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d9c5eecdb3c740e65038651db7c686b10d76d1bc","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ee1778ba0f5cb53be771f97017d01eb356c797bf","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f1e89a943ee574d0f2f16246eb3f2d7330fdeb03","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f5c68875e25f331e497ddfbe81e2d8163a87f136","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/fc32be9ac2788524c6b24efd681cce7a6e731a92","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-63917","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}