{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-64542",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-07-19T15:36:31.795Z",
        "datePublished": "2026-07-27T20:10:34.994Z",
        "dateUpdated": "2026-08-19T16:28:25.885Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-19T16:28:25.885Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: ndisc: fix NULL deref in accept_untracked_na()\n\naccept_untracked_na() re-fetches the inet6_dev with __in6_dev_get(dev)\nand dereferences idev->cnf.accept_untracked_na without a NULL check,\neven though its only caller ndisc_recv_na() already fetched and\nNULL-checked idev for the same device.\n\nBoth reads of dev->ip6_ptr run in the same RCU read-side critical\nsection, but a concurrent addrconf_ifdown() can clear dev->ip6_ptr\nbetween them: lowering the MTU below IPV6_MIN_MTU calls addrconf_ifdown()\nwithout the synchronize_net() that orders the unregister path, so the\nre-fetch returns NULL and oopses:\n\n BUG: KASAN: null-ptr-deref in ndisc_recv_na (net/ipv6/ndisc.c:974)\n Read of size 4 at addr 0000000000000364\n Call Trace:\n  <IRQ>\n  ndisc_recv_na (net/ipv6/ndisc.c:974)\n  icmpv6_rcv (net/ipv6/icmp.c:1193)\n  ip6_protocol_deliver_rcu (net/ipv6/ip6_input.c:479)\n  ip6_input_finish (net/ipv6/ip6_input.c:534)\n  ip6_input (net/ipv6/ip6_input.c:545)\n  ip6_mc_input (net/ipv6/ip6_input.c:635)\n  ipv6_rcv (net/ipv6/ip6_input.c:351)\n  </IRQ>\n\nIt is reachable by an unprivileged user via a network namespace.\n\nPass the caller's already validated idev instead of re-fetching it; the\nidev stays alive for the whole RCU critical section, so it is safe even\nafter dev->ip6_ptr has been cleared."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/ipv6/ndisc.c"
                    ],
                    "versions": [
                        {
                            "version": "aaa5f515b16b6b3e137779ffb4c9558bb58c1e75",
                            "lessThan": "e5ba3017e46f275ad347e762e8eecacec5efa41d",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "aaa5f515b16b6b3e137779ffb4c9558bb58c1e75",
                            "lessThan": "160d3f0d7a556ceae505dcab521a37057b4ce28f",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "aaa5f515b16b6b3e137779ffb4c9558bb58c1e75",
                            "lessThan": "62c719203cb521b64fab74da94a81bdde5c18808",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "aaa5f515b16b6b3e137779ffb4c9558bb58c1e75",
                            "lessThan": "a6450f7cfae57b382cbaf66a577765c9a88b3c58",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "aaa5f515b16b6b3e137779ffb4c9558bb58c1e75",
                            "lessThan": "63d1c23764de2309cedbb779c75188d257a09d9b",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "aaa5f515b16b6b3e137779ffb4c9558bb58c1e75",
                            "lessThan": "d186e942365acece7c56d39da05dd63bf95b280a",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/ipv6/ndisc.c"
                    ],
                    "versions": [
                        {
                            "version": "6.0",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.0",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.1.183",
                            "lessThanOrEqual": "6.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.148",
                            "lessThanOrEqual": "6.6.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.97",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.40",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.1.5",
                            "lessThanOrEqual": "7.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.0",
                                    "versionEndExcluding": "6.1.183"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.0",
                                    "versionEndExcluding": "6.6.148"
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                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.0",
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                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.0",
                                    "versionEndExcluding": "7.2"
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            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/e5ba3017e46f275ad347e762e8eecacec5efa41d"
                },
                {
                    "url": "https://git.kernel.org/stable/c/160d3f0d7a556ceae505dcab521a37057b4ce28f"
                },
                {
                    "url": "https://git.kernel.org/stable/c/62c719203cb521b64fab74da94a81bdde5c18808"
                },
                {
                    "url": "https://git.kernel.org/stable/c/a6450f7cfae57b382cbaf66a577765c9a88b3c58"
                },
                {
                    "url": "https://git.kernel.org/stable/c/63d1c23764de2309cedbb779c75188d257a09d9b"
                },
                {
                    "url": "https://git.kernel.org/stable/c/d186e942365acece7c56d39da05dd63bf95b280a"
                }
            ],
            "title": "ipv6: ndisc: fix NULL deref in accept_untracked_na()",
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