{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2025-21891",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2024-12-29T08:45:45.783Z",
        "datePublished": "2025-03-27T14:57:17.267Z",
        "dateUpdated": "2026-05-11T21:08:31.288Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-05-11T21:08:31.288Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipvlan: ensure network headers are in skb linear part\n\nsyzbot found that ipvlan_process_v6_outbound() was assuming\nthe IPv6 network header isis present in skb->head [1]\n\nAdd the needed pskb_network_may_pull() calls for both\nIPv4 and IPv6 handlers.\n\n[1]\nBUG: KMSAN: uninit-value in __ipv6_addr_type+0xa2/0x490 net/ipv6/addrconf_core.c:47\n  __ipv6_addr_type+0xa2/0x490 net/ipv6/addrconf_core.c:47\n  ipv6_addr_type include/net/ipv6.h:555 [inline]\n  ip6_route_output_flags_noref net/ipv6/route.c:2616 [inline]\n  ip6_route_output_flags+0x51/0x720 net/ipv6/route.c:2651\n  ip6_route_output include/net/ip6_route.h:93 [inline]\n  ipvlan_route_v6_outbound+0x24e/0x520 drivers/net/ipvlan/ipvlan_core.c:476\n  ipvlan_process_v6_outbound drivers/net/ipvlan/ipvlan_core.c:491 [inline]\n  ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:541 [inline]\n  ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:605 [inline]\n  ipvlan_queue_xmit+0xd72/0x1780 drivers/net/ipvlan/ipvlan_core.c:671\n  ipvlan_start_xmit+0x5b/0x210 drivers/net/ipvlan/ipvlan_main.c:223\n  __netdev_start_xmit include/linux/netdevice.h:5150 [inline]\n  netdev_start_xmit include/linux/netdevice.h:5159 [inline]\n  xmit_one net/core/dev.c:3735 [inline]\n  dev_hard_start_xmit+0x247/0xa20 net/core/dev.c:3751\n  sch_direct_xmit+0x399/0xd40 net/sched/sch_generic.c:343\n  qdisc_restart net/sched/sch_generic.c:408 [inline]\n  __qdisc_run+0x14da/0x35d0 net/sched/sch_generic.c:416\n  qdisc_run+0x141/0x4d0 include/net/pkt_sched.h:127\n  net_tx_action+0x78b/0x940 net/core/dev.c:5484\n  handle_softirqs+0x1a0/0x7c0 kernel/softirq.c:561\n  __do_softirq+0x14/0x1a kernel/softirq.c:595\n  do_softirq+0x9a/0x100 kernel/softirq.c:462\n  __local_bh_enable_ip+0x9f/0xb0 kernel/softirq.c:389\n  local_bh_enable include/linux/bottom_half.h:33 [inline]\n  rcu_read_unlock_bh include/linux/rcupdate.h:919 [inline]\n  __dev_queue_xmit+0x2758/0x57d0 net/core/dev.c:4611\n  dev_queue_xmit include/linux/netdevice.h:3311 [inline]\n  packet_xmit+0x9c/0x6c0 net/packet/af_packet.c:276\n  packet_snd net/packet/af_packet.c:3132 [inline]\n  packet_sendmsg+0x93e0/0xa7e0 net/packet/af_packet.c:3164\n  sock_sendmsg_nosec net/socket.c:718 [inline]"
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/net/ipvlan/ipvlan_core.c"
                    ],
                    "versions": [
                        {
                            "version": "2ad7bf3638411cb547f2823df08166c13ab04269",
                            "lessThan": "5b8dea8d1612dc7151d2457d7d2e6a69820309bf",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "2ad7bf3638411cb547f2823df08166c13ab04269",
                            "lessThan": "4ec48f812804f370f622e0874e6dd8fcc58241cd",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "2ad7bf3638411cb547f2823df08166c13ab04269",
                            "lessThan": "5353fd89663c48f56bdff975c562cfe78b1a2e4c",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "2ad7bf3638411cb547f2823df08166c13ab04269",
                            "lessThan": "e2a4f76a2d8a44816ecd25bcbdb47b786d621974",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "2ad7bf3638411cb547f2823df08166c13ab04269",
                            "lessThan": "27843ce6ba3d3122b65066550fe33fb8839f8aef",
                            "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/ipvlan/ipvlan_core.c"
                    ],
                    "versions": [
                        {
                            "version": "3.19",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "3.19",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.1.130",
                            "lessThanOrEqual": "6.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.81",
                            "lessThanOrEqual": "6.6.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.18",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.13.6",
                            "lessThanOrEqual": "6.13.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.14",
                            "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": "3.19",
                                    "versionEndExcluding": "6.1.130"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "3.19",
                                    "versionEndExcluding": "6.6.81"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "3.19",
                                    "versionEndExcluding": "6.12.18"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "3.19",
                                    "versionEndExcluding": "6.13.6"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "3.19",
                                    "versionEndExcluding": "6.14"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/5b8dea8d1612dc7151d2457d7d2e6a69820309bf"
                },
                {
                    "url": "https://git.kernel.org/stable/c/4ec48f812804f370f622e0874e6dd8fcc58241cd"
                },
                {
                    "url": "https://git.kernel.org/stable/c/5353fd89663c48f56bdff975c562cfe78b1a2e4c"
                },
                {
                    "url": "https://git.kernel.org/stable/c/e2a4f76a2d8a44816ecd25bcbdb47b786d621974"
                },
                {
                    "url": "https://git.kernel.org/stable/c/27843ce6ba3d3122b65066550fe33fb8839f8aef"
                }
            ],
            "title": "ipvlan: ensure network headers are in skb linear part",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "cvssV3_1": {
                            "scope": "UNCHANGED",
                            "version": "3.1",
                            "baseScore": 5.5,
                            "attackVector": "LOCAL",
                            "baseSeverity": "MEDIUM",
                            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                            "integrityImpact": "NONE",
                            "userInteraction": "NONE",
                            "attackComplexity": "LOW",
                            "availabilityImpact": "HIGH",
                            "privilegesRequired": "LOW",
                            "confidentialityImpact": "NONE"
                        }
                    },
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "id": "CVE-2025-21891",
                                "role": "CISA Coordinator",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "version": "2.0.3",
                                "timestamp": "2025-10-01T19:25:21.205802Z"
                            }
                        }
                    }
                ],
                "problemTypes": [
                    {
                        "descriptions": [
                            {
                                "lang": "en",
                                "type": "CWE",
                                "cweId": "CWE-908",
                                "description": "CWE-908 Use of Uninitialized Resource"
                            }
                        ]
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2025-10-01T19:26:36.702Z"
                }
            },
            {
                "title": "CVE Program Container",
                "references": [
                    {
                        "url": "https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html"
                    }
                ],
                "providerMetadata": {
                    "orgId": "af854a3a-2127-422b-91ae-364da2661108",
                    "shortName": "CVE",
                    "dateUpdated": "2025-11-03T19:38:41.627Z"
                }
            }
        ]
    }
}