{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-74743",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-08-15T05:44:03.930Z",
        "datePublished": "2026-08-26T14:36:54.175Z",
        "dateUpdated": "2026-08-26T14:36:54.175Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-26T14:36:54.175Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmacvlan: inherit needed_headroom and needed_tailroom from lowerdev\n\nmacvlan devices inherit hard_header_len from lowerdev during macvlan_init(),\nbut leave needed_headroom and needed_tailroom set to 0.\n\nWhen the underlying lowerdev requires extra headroom or tailroom for\nheaders/trailers (e.g. macsec, ipsec, wireguard, tunnels, or veth with rx\nheadroom), upper layers calculating packet headroom and tailroom fail to\nreserve sufficient space.\n\nThis can result in reallocation overhead, skb headroom underflows, or KASAN\nslab-use-after-free crashes when dev_hard_header() / macvlan_hard_header()\nprepends header data or when lower devices append tailroom.\n\nFix this by:\n1. Inheriting needed_headroom and needed_tailroom from lowerdev in macvlan_init().\n2. Propagating needed_headroom and needed_tailroom updates to attached macvlans\n   in macvlan_device_event() when receiving NETDEV_FEAT_CHANGE events."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/net/macvlan.c"
                    ],
                    "versions": [
                        {
                            "version": "b863ceb7ddcea8c55fcf1d7b2ac591d50aa7ed53",
                            "lessThan": "8cd90e850e434577bf6774778657d26d6995e53f",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "b863ceb7ddcea8c55fcf1d7b2ac591d50aa7ed53",
                            "lessThan": "28afc87bd8da0b3348bbbd834c8a89e83712cf5e",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "b863ceb7ddcea8c55fcf1d7b2ac591d50aa7ed53",
                            "lessThan": "8f6a05dbac05725e0786701eb04778c5bdbe4eaa",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "b863ceb7ddcea8c55fcf1d7b2ac591d50aa7ed53",
                            "lessThan": "96fa90b74385b7f2b0d97251dd43d5ee6ca44668",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "b863ceb7ddcea8c55fcf1d7b2ac591d50aa7ed53",
                            "lessThan": "bc9a00fb78e32bccc39d763bfd13a450705bac5d",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "b863ceb7ddcea8c55fcf1d7b2ac591d50aa7ed53",
                            "lessThan": "cef51860becd9700217c81732ca1eb1ea6ed6fe1",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/net/macvlan.c"
                    ],
                    "versions": [
                        {
                            "version": "2.6.23",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "2.6.23",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.1.184",
                            "lessThanOrEqual": "6.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.153",
                            "lessThanOrEqual": "6.6.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.105",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.46",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.1.10",
                            "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": "2.6.23",
                                    "versionEndExcluding": "6.1.184"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.23",
                                    "versionEndExcluding": "6.6.153"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.23",
                                    "versionEndExcluding": "6.12.105"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.23",
                                    "versionEndExcluding": "6.18.46"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.23",
                                    "versionEndExcluding": "7.1.10"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.23",
                                    "versionEndExcluding": "7.2"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/8cd90e850e434577bf6774778657d26d6995e53f"
                },
                {
                    "url": "https://git.kernel.org/stable/c/28afc87bd8da0b3348bbbd834c8a89e83712cf5e"
                },
                {
                    "url": "https://git.kernel.org/stable/c/8f6a05dbac05725e0786701eb04778c5bdbe4eaa"
                },
                {
                    "url": "https://git.kernel.org/stable/c/96fa90b74385b7f2b0d97251dd43d5ee6ca44668"
                },
                {
                    "url": "https://git.kernel.org/stable/c/bc9a00fb78e32bccc39d763bfd13a450705bac5d"
                },
                {
                    "url": "https://git.kernel.org/stable/c/cef51860becd9700217c81732ca1eb1ea6ed6fe1"
                }
            ],
            "title": "macvlan: inherit needed_headroom and needed_tailroom from lowerdev",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        }
    }
}