netfilter: nft_tunnel: fix use-after-free on object destroy_CVE-2026-53212

{
    "lastseen": "",
    "description": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nft_tunnel: fix use-after-free on object destroy\n\nnft_tunnel_obj_destroy() calls metadata_dst_free() which directly\nkfree()s the metadata_dst, ignoring the dst_entry refcount. Packets\nthat took a reference via dst_hold() in nft_tunnel_obj_eval() and\nare still queued (e.g. in a netem qdisc) are left with a dangling\npointer. When these packets are eventually dequeued, dst_release()\noperates on freed memory.\n\nReplace metadata_dst_free() with dst_release() so the metadata_dst\nis freed only after all references are dropped. The dst subsystem\nalready handles metadata_dst cleanup in dst_destroy() when\nDST_METADATA is set.",
    "published": "2026-06-25T08:39:16.888Z",
    "modified": "2026-06-28T06:40:26.976Z",
    "type": "cve",
    "title": "netfilter: nft_tunnel: fix use-after-free on object destroy",
    "source": "Linux",
    "references": "https://git.kernel.org/stable/c/349df61526d2e39decc685d246202e3e284cfe05\nhttps://git.kernel.org/stable/c/55b79b1ae42372012413ce0413181d26679b17ef\nhttps://git.kernel.org/stable/c/5e9ee18b27fde88cb6148202b33916c66693fe82\nhttps://git.kernel.org/stable/c/8767fe4079affa74314d7eb3220e700150289842\nhttps://git.kernel.org/stable/c/fda6573a46ad24f35348e024905ee5bdf729797e\nhttps://git.kernel.org/stable/c/941d7394efda5e054e2d6f3e0dd0f6a9ba19aaa3\nhttps://git.kernel.org/stable/c/f9a0e4b61054cde89a2a77845293c726cc07cc43\nhttps://git.kernel.org/stable/c/c32b26aaa2f9216520a38b3f4bfeec846eb3eb8a",
    "id": "CVE-2026-53212",
    "bulletinFamily": "",
    "cwe": null,
    "cvelist": null,
    "sourceData": "Linux Linux af308b94a2a4a5a27bec9028354c4df444a7c8ba\nLinux Linux af308b94a2a4a5a27bec9028354c4df444a7c8ba\nLinux Linux af308b94a2a4a5a27bec9028354c4df444a7c8ba\nLinux Linux af308b94a2a4a5a27bec9028354c4df444a7c8ba\nLinux Linux af308b94a2a4a5a27bec9028354c4df444a7c8ba\nLinux Linux af308b94a2a4a5a27bec9028354c4df444a7c8ba\nLinux Linux af308b94a2a4a5a27bec9028354c4df444a7c8ba\nLinux Linux af308b94a2a4a5a27bec9028354c4df444a7c8ba\nLinux Linux 4.19",
    "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": "",
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        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
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            "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": "af308b94a2a4a5a27bec9028354c4df444a7c8ba",
    "vendor": "Linux",
    "ai_description": "",
    "ai_severity": "",
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    "ai_score": 0
}