{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: f_ncm: Fix net_device lifecycle with device_move\n\nThe network device outlived its parent gadget device during\ndisconnection, resulting in dangling sysfs links and null pointer\ndereference problems.\n\nA prior attempt to solve this by removing SET_NETDEV_DEV entirely [1]\nwas reverted due to power management ordering concerns and a NO-CARRIER\nregression.\n\nA subsequent attempt to defer net_device allocation to bind [2] broke\n1:1 mapping between function instance and network device, making it\nimpossible for configfs to report the resolved interface name. This\nresults in a regression where the DHCP server fails on pmOS.\n\nUse device_move to reparent the net_device between the gadget device and\n/sys/devices/virtual/ across bind/unbind cycles. This preserves the\nnetwork interface across USB reconnection, allowing the DHCP server to\nretain their binding.\n\nIntroduce gether_attach_gadget()/gether_detach_gadget() helpers and use\n__free(detach_gadget) macro to undo attachment on bind failure. The\nbind_count ensures device_move executes only on the first bind.\n\n[1] https://lore.kernel.org/lkml/f2a4f9847617a0929d62025748384092e5f35cce.camel@crapouillou.net/\n[2] https://lore.kernel.org/linux-usb/795ea759-7eaf-4f78-81f4-01ffbf2d7961@ixit.cz/"
    }
  ],
  "id": "CVE-2026-43421",
  "lastModified": "2026-05-12T14:10:27.343",
  "metrics": {},
  "published": "2026-05-08T15:16:54.173",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/85acaba2f42b557499bab3608307f17bf13beb69"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/93f116c3393a22acab96ad1bef12b2572eb80ca4"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/e584cb58a2ea7ff4d3a4bc43d5ca512ed3ecb77d"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/ec35c1969650e7cb6c8a91020e568ed46e3551b0"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Undergoing Analysis"
}

{
  "affected": [],
  "aliases": [
    "CVE-2026-43421"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-08T15:16:54Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: f_ncm: Fix net_device lifecycle with device_move\n\nThe network device outlived its parent gadget device during\ndisconnection, resulting in dangling sysfs links and null pointer\ndereference problems.\n\nA prior attempt to solve this by removing SET_NETDEV_DEV entirely [1]\nwas reverted due to power management ordering concerns and a NO-CARRIER\nregression.\n\nA subsequent attempt to defer net_device allocation to bind [2] broke\n1:1 mapping between function instance and network device, making it\nimpossible for configfs to report the resolved interface name. This\nresults in a regression where the DHCP server fails on pmOS.\n\nUse device_move to reparent the net_device between the gadget device and\n/sys/devices/virtual/ across bind/unbind cycles. This preserves the\nnetwork interface across USB reconnection, allowing the DHCP server to\nretain their binding.\n\nIntroduce gether_attach_gadget()/gether_detach_gadget() helpers and use\n__free(detach_gadget) macro to undo attachment on bind failure. The\nbind_count ensures device_move executes only on the first bind.\n\n[1] https://lore.kernel.org/lkml/f2a4f9847617a0929d62025748384092e5f35cce.camel@crapouillou.net/\n[2] https://lore.kernel.org/linux-usb/795ea759-7eaf-4f78-81f4-01ffbf2d7961@ixit.cz/",
  "id": "GHSA-w77g-4c35-prwp",
  "modified": "2026-05-08T15:31:28Z",
  "published": "2026-05-08T15:31:28Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-43421"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/85acaba2f42b557499bab3608307f17bf13beb69"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/93f116c3393a22acab96ad1bef12b2572eb80ca4"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e584cb58a2ea7ff4d3a4bc43d5ca512ed3ecb77d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ec35c1969650e7cb6c8a91020e568ed46e3551b0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

{
  "document": {
    "category": "csaf_vex",
    "csaf_version": "2.0",
    "distribution": {
      "text": "Public",
      "tlp": {
        "label": "WHITE",
        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "en-US",
    "notes": [
      {
        "category": "general",
        "text": "To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle",
        "title": "Additional Resources"
      },
      {
        "category": "legal_disclaimer",
        "text": "The information provided in the Microsoft Knowledge Base is provided \\\"as is\\\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.",
        "title": "Disclaimer"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "secure@microsoft.com",
      "name": "Microsoft Security Response Center",
      "namespace": "https://msrc.microsoft.com"
    },
    "references": [
      {
        "category": "self",
        "summary": "CVE-2026-43421 usb: gadget: f_ncm: Fix net_device lifecycle with device_move - VEX",
        "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-43421.json"
      },
      {
        "category": "external",
        "summary": "Microsoft Support Lifecycle",
        "url": "https://support.microsoft.com/lifecycle"
      },
      {
        "category": "external",
        "summary": "Common Vulnerability Scoring System",
        "url": "https://www.first.org/cvss"
      }
    ],
    "title": "usb: gadget: f_ncm: Fix net_device lifecycle with device_move",
    "tracking": {
      "current_release_date": "2026-05-19T01:39:13.000Z",
      "generator": {
        "date": "2026-05-19T07:12:12.390Z",
        "engine": {
          "name": "MSRC Generator",
          "version": "1.0"
        }
      },
      "id": "msrc_CVE-2026-43421",
      "initial_release_date": "2026-05-02T00:00:00.000Z",
      "revision_history": [
        {
          "date": "2026-05-09T01:04:04.000Z",
          "legacy_version": "1",
          "number": "1",
          "summary": "Information published."
        },
        {
          "date": "2026-05-11T01:52:10.000Z",
          "legacy_version": "2",
          "number": "2",
          "summary": "Information published."
        },
        {
          "date": "2026-05-17T14:51:21.000Z",
          "legacy_version": "3",
          "number": "3",
          "summary": "Information published."
        },
        {
          "date": "2026-05-19T01:39:13.000Z",
          "legacy_version": "4",
          "number": "4",
          "summary": "Information published."
        }
      ],
      "status": "final",
      "version": "4"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version",
                "name": "3.0",
                "product": {
                  "name": "Azure Linux 3.0",
                  "product_id": "17084"
                }
              }
            ],
            "category": "product_name",
            "name": "Azure Linux"
          },
          {
            "category": "product_name",
            "name": "azl3 kernel 0:6.6.139.1-1.azl3",
            "product": {
              "name": "azl3 kernel 0:6.6.139.1-1.azl3",
              "product_id": "1"
            }
          }
        ],
        "category": "vendor",
        "name": "Microsoft"
      }
    ],
    "relationships": [
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "azl3 kernel 0:6.6.139.1-1.azl3 as a component of Azure Linux 3.0",
          "product_id": "17084-1"
        },
        "product_reference": "1",
        "relates_to_product_reference": "17084"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-43421",
      "flags": [
        {
          "label": "vulnerable_code_not_present",
          "product_ids": [
            "17084-1"
          ]
        }
      ],
      "notes": [
        {
          "category": "general",
          "text": "Linux",
          "title": "Assigning CNA"
        }
      ],
      "product_status": {
        "known_not_affected": [
          "17084-1"
        ],
        "under_investigation": [
          "17084-3",
          "17084-2"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "CVE-2026-43421 usb: gadget: f_ncm: Fix net_device lifecycle with device_move - VEX",
          "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-43421.json"
        }
      ],
      "title": "usb: gadget: f_ncm: Fix net_device lifecycle with device_move"
    }
  ]
}