{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-53012",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-06-09T07:44:35.378Z",
        "datePublished": "2026-06-24T16:29:22.973Z",
        "dateUpdated": "2026-06-24T16:29:22.973Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-06-24T16:29:22.973Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnexthop: fix IPv6 route referencing IPv4 nexthop\n\nsyzbot reported a panic [1] [2].\n\nWhen an IPv6 nexthop is replaced with an IPv4 nexthop, the has_v4 flag\nof all groups containing this nexthop is not updated. This is because\nnh_group_v4_update is only called when replacing AF_INET to AF_INET6,\nbut the reverse direction (AF_INET6 to AF_INET) is missed.\n\nThis allows a stale has_v4=false to bypass fib6_check_nexthop, causing\nIPv6 routes to be attached to groups that effectively contain only AF_INET\nmembers. Subsequent route lookups then call nexthop_fib6_nh() which\nreturns NULL for the AF_INET member, leading to a NULL pointer\ndereference.\n\nFix by calling nh_group_v4_update whenever the family changes, not just\nAF_INET to AF_INET6.\n\nReproducer:\n\t# AF_INET6 blackhole\n\tip -6 nexthop add id 1 blackhole\n\t# group with has_v4=false\n\tip nexthop add id 100 group 1\n\t# replace with AF_INET (no -6), has_v4 stays false\n\tip nexthop replace id 1 blackhole\n\t# pass stale has_v4 check\n\tip -6 route add 2001:db8::/64 nhid 100\n\t# panic\n\tping -6 2001:db8::1\n\n[1] https://syzkaller.appspot.com/bug?id=e17283eb2f8dcf3dd9b47fe6f67a95f71faadad0\n[2] https://syzkaller.appspot.com/bug?id=8699b6ae54c9f35837d925686208402949e12ef3"
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/ipv4/nexthop.c"
                    ],
                    "versions": [
                        {
                            "version": "7bf4796dd09984ad1612877a82d0d139c70ae27f",
                            "lessThan": "ceffe81a0be92afc0cd1340bc8ca46559cce9bb4",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "7bf4796dd09984ad1612877a82d0d139c70ae27f",
                            "lessThan": "9c2d6770a5f4545a307eb66979bef7656a34d621",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "7bf4796dd09984ad1612877a82d0d139c70ae27f",
                            "lessThan": "6275796f22bb382f3e9aa58ed0b4ef7bdad78cb8",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "7bf4796dd09984ad1612877a82d0d139c70ae27f",
                            "lessThan": "aaac3bed034239e1d75732211d9b05f30b0b4f35",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "7bf4796dd09984ad1612877a82d0d139c70ae27f",
                            "lessThan": "ad85961004fd4bd2f31209ac4b07612c6cefb9e7",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "7bf4796dd09984ad1612877a82d0d139c70ae27f",
                            "lessThan": "613c8f4a501421dd258b07ea614205d4e16ec845",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "7bf4796dd09984ad1612877a82d0d139c70ae27f",
                            "lessThan": "b3b7e850e1541f0520c4a12ec884255c30427ff6",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "7bf4796dd09984ad1612877a82d0d139c70ae27f",
                            "lessThan": "29c95185ba32b621fbc3800fb86e7dc3edf5c2be",
                            "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/ipv4/nexthop.c"
                    ],
                    "versions": [
                        {
                            "version": "5.3",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "5.3",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "5.10.258",
                            "lessThanOrEqual": "5.10.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "5.15.209",
                            "lessThanOrEqual": "5.15.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.1.175",
                            "lessThanOrEqual": "6.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.141",
                            "lessThanOrEqual": "6.6.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.91",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.33",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.0.10",
                            "lessThanOrEqual": "7.0.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.1",
                            "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": "5.3",
                                    "versionEndExcluding": "5.10.258"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.3",
                                    "versionEndExcluding": "5.15.209"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.3",
                                    "versionEndExcluding": "6.1.175"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.3",
                                    "versionEndExcluding": "6.6.141"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.3",
                                    "versionEndExcluding": "6.12.91"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.3",
                                    "versionEndExcluding": "6.18.33"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.3",
                                    "versionEndExcluding": "7.0.10"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.3",
                                    "versionEndExcluding": "7.1"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/ceffe81a0be92afc0cd1340bc8ca46559cce9bb4"
                },
                {
                    "url": "https://git.kernel.org/stable/c/9c2d6770a5f4545a307eb66979bef7656a34d621"
                },
                {
                    "url": "https://git.kernel.org/stable/c/6275796f22bb382f3e9aa58ed0b4ef7bdad78cb8"
                },
                {
                    "url": "https://git.kernel.org/stable/c/aaac3bed034239e1d75732211d9b05f30b0b4f35"
                },
                {
                    "url": "https://git.kernel.org/stable/c/ad85961004fd4bd2f31209ac4b07612c6cefb9e7"
                },
                {
                    "url": "https://git.kernel.org/stable/c/613c8f4a501421dd258b07ea614205d4e16ec845"
                },
                {
                    "url": "https://git.kernel.org/stable/c/b3b7e850e1541f0520c4a12ec884255c30427ff6"
                },
                {
                    "url": "https://git.kernel.org/stable/c/29c95185ba32b621fbc3800fb86e7dc3edf5c2be"
                }
            ],
            "title": "nexthop: fix IPv6 route referencing IPv4 nexthop",
            "x_generator": {
                "engine": "bippy-1.2.0"
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        }
    }
}