ip6_gre: Use cached t->net in ip6erspan_changelink()._CVE-2026-46120

{
    "lastseen": "",
    "description": "In the Linux kernel, the following vulnerability has been resolved:\n\nip6_gre: Use cached t->net 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->net; only ip6erspan_changelink() has the wrong shape.",
    "published": "2026-05-28T09:35:35.385Z",
    "modified": "2026-05-30T10:47:58.919Z",
    "type": "cve",
    "title": "ip6_gre: Use cached t->net in ip6erspan_changelink().",
    "source": "Linux",
    "references": "https://git.kernel.org/stable/c/eca62bb0569de4d43a4dac06a2092a9d4ca1d702\nhttps://git.kernel.org/stable/c/311fdd26eb4443d43b909cc67a10f3a5fd1b21b2\nhttps://git.kernel.org/stable/c/e70cfb40c3a99b232cd42c6a6a10f0d8e039dc82\nhttps://git.kernel.org/stable/c/cf7fc624329e76c6394653d12353e1d033adea91\nhttps://git.kernel.org/stable/c/1d324c2f43f70c965f25c58cc3611c779adbe47e",
    "id": "CVE-2026-46120",
    "bulletinFamily": "",
    "cwe": null,
    "cvelist": null,
    "sourceData": "Linux Linux 2d665034f239412927b1e71329f20f001c92da09\nLinux Linux 2d665034f239412927b1e71329f20f001c92da09\nLinux Linux 2d665034f239412927b1e71329f20f001c92da09\nLinux Linux 2d665034f239412927b1e71329f20f001c92da09\nLinux Linux 2d665034f239412927b1e71329f20f001c92da09\nLinux Linux c6d72628352c949629af619b77b042e0fb5245e7\nLinux Linux 4.16.12\nLinux Linux 4.17",
    "sourceHref": "",
    "cvss": {
        "score": 7.8,
        "severity": "HIGH",
        "vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
        "attackVector": "",
        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
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            "privilegesRequired": "",
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            "confidentialityImpact": "",
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            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "Linux",
    "version": "2d665034f239412927b1e71329f20f001c92da09",
    "vendor": "Linux",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
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    "ai_score": 0
}