{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-72429",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-08-09T03:40:39.928Z",
        "datePublished": "2026-08-15T05:56:45.530Z",
        "dateUpdated": "2026-08-17T05:44:08.737Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-17T05:44:08.737Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: ioam: fix type confusion of dst_entry\n\nIOAM uses a dummy dst_entry(null_dst) to mark that the destination should\nnot be changed after the transformation. This dst is stored in the IOAM lwt\nstate and may be passed to dst_cache_set_ip6().\n\nHowever, the IPv6 dst cache path eventually calls rt6_get_cookie(), which\ntreats the dst_entry as part of a struct rt6_info. Since the null_dst was\nembedded directly as a struct dst_entry in struct ioam6_lwt, this resulted\nin an invalid cast and rt6_get_cookie() reading fields from the wrong\nobject.\n\nIn practice, the wrong cookie is not used while dst->obsolete is zero, but\nrt6_get_cookie() may also access per-cpu value when rt->sernum is\nzero. In this case, rt->sernum aliases ioam6_lwt::cache::reset_ts, which\ncan become zero, making this a potential invalid pointer access.\n\nFix this by embedding a full struct rt6_info for the dummy IPv6 route and\npassing its dst member to the dst APIs."
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
                        "baseScore": 9.8,
                        "baseSeverity": "CRITICAL"
                    },
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "AV:N - The flaw is in ioam6_output() on the IPv6 transmit path (lwtunnel_output→dst_output), reachable when remotely sourced IPv6 packets are forwarded or locally output through an IOAM6 LWT route on internet-facing or LAN routers.\nAC:L - Once IOAM6 LWT inline routes exist, an attacker can reliably trigger the null_dst dst_cache_set_ip6() path by sending IPv6 traffic that misses the per-CPU dst cache, without races or uncontrollable memory layout.\nPR:N - Exploitation requires only the ability to send IPv6 packets; IOAM6 LWT route and namespace setup needs CAP_NET_ADMIN on the victim but is an operator deployment prerequisite, not attacker privilege.\nUI:N - No victim user action is required beyond normal network operation; crafted or high-volume IPv6 packets alone drive the vulnerable output path.\nS:U - Impact is kernel memory corruption and crash within the host kernel; it does not cross VM, container, or IOMMU security boundaries.\nC:H - Type confusion makes rt6_get_cookie() treat ioam6_lwt fields as rt6_info members and chase a misinterpreted fib6_info pointer via fib6_get_cookie_safe(), enabling out-of-bounds kernel memory reads.\nI:H - Casting a standalone dst_entry to rt6_info is type confusion that corrupts pointer interpretation and dst_cache cookie state, a class exploitable toward arbitrary kernel writes or control-flow hijack.\nA:H - The confused rt6_info layout can dereference invalid fib6_info/fib6_node pointers, causing kernel oops or panic; memory corruption in the networking fast path also risks host-wide denial of service."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/ipv6/ioam6_iptunnel.c"
                    ],
                    "versions": [
                        {
                            "version": "47ce7c854563fe8450e9cb8dcd62c6470e28076b",
                            "lessThan": "ea24f911ead85ba3d570a31e37c52b6c949f6928",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "47ce7c854563fe8450e9cb8dcd62c6470e28076b",
                            "lessThan": "5a3b2ee1e96d0580a8ed8deda6dfa430604f9ab0",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "47ce7c854563fe8450e9cb8dcd62c6470e28076b",
                            "lessThan": "9ed19e11d2146076d117d51a940643990118449b",
                            "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/ioam6_iptunnel.c"
                    ],
                    "versions": [
                        {
                            "version": "6.16",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.16",
                            "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": "6.16",
                                    "versionEndExcluding": "6.18.40"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.16",
                                    "versionEndExcluding": "7.1.5"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.16",
                                    "versionEndExcluding": "7.2"
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            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/ea24f911ead85ba3d570a31e37c52b6c949f6928"
                },
                {
                    "url": "https://git.kernel.org/stable/c/5a3b2ee1e96d0580a8ed8deda6dfa430604f9ab0"
                },
                {
                    "url": "https://git.kernel.org/stable/c/9ed19e11d2146076d117d51a940643990118449b"
                }
            ],
            "title": "ipv6: ioam: fix type confusion of dst_entry",
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}