{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: rtnetlink: zero ifla_vf_broadcast to avoid stack infoleak in rtnl_fill_vfinfo\n\nrtnl_fill_vfinfo() declares struct ifla_vf_broadcast on the stack\nwithout initialisation:\n\n\tstruct ifla_vf_broadcast vf_broadcast;\n\nThe struct contains a single fixed 32-byte field:\n\n\t/* include/uapi/linux/if_link.h */\n\tstruct ifla_vf_broadcast {\n\t\t__u8 broadcast[32];\n\t};\n\nThe function then copies dev-\u003ebroadcast into it using dev-\u003eaddr_len\nas the length:\n\n\tmemcpy(vf_broadcast.broadcast, dev-\u003ebroadcast, dev-\u003eaddr_len);\n\nOn Ethernet devices (the overwhelming majority of SR-IOV NICs)\ndev-\u003eaddr_len is 6, so only the first 6 bytes of broadcast[] are\nwritten. The remaining 26 bytes retain whatever was previously on\nthe kernel stack. The full struct is then handed to userspace via:\n\n\tnla_put(skb, IFLA_VF_BROADCAST,\n\t\tsizeof(vf_broadcast), \u0026vf_broadcast)\n\nleaking up to 26 bytes of uninitialised kernel stack per VF per\nRTM_GETLINK request, repeatable.\n\nThe other vf_* structs in the same function are explicitly zeroed\nfor exactly this reason - see the memset() calls for ivi,\nvf_vlan_info, node_guid and port_guid a few lines above.\nvf_broadcast was simply missed when it was added.\n\nReachability: any unprivileged local process can open AF_NETLINK /\nNETLINK_ROUTE without capabilities and send RTM_GETLINK with an\nIFLA_EXT_MASK attribute carrying RTEXT_FILTER_VF. The kernel walks\neach VF and emits IFLA_VF_BROADCAST, leaking 26 bytes of stack per\nVF per request. Stack residue at this call site can include return\naddresses and transient sensitive data; KASAN with stack\ninstrumentation, or KMSAN, will flag the nla_put() when reproduced.\n\nZero the on-stack struct before the partial memcpy, matching the\nexisting pattern used for the other vf_* structs in the same\nfunction."
    }
  ],
  "id": "CVE-2026-46132",
  "lastModified": "2026-05-28T13:44:01.663",
  "metrics": {},
  "published": "2026-05-28T10:16:28.753",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/0653c0516234c8258975d268a749115fc0f0ff00"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/38bcc21f52246badb3154b6158dcb381d98de011"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/4b9e327991815e128ad3af75c3a04630a63ce3e0"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/c5b1b92ab7eff1a6e8c507ddde6fd02fabd0cfa8"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/fbe0e6197225e6a83cf113a67a4b425f8de0bcd5"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Awaiting Analysis"
}

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-46132"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-28T10:16:28Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: rtnetlink: zero ifla_vf_broadcast to avoid stack infoleak in rtnl_fill_vfinfo\n\nrtnl_fill_vfinfo() declares struct ifla_vf_broadcast on the stack\nwithout initialisation:\n\n\tstruct ifla_vf_broadcast vf_broadcast;\n\nThe struct contains a single fixed 32-byte field:\n\n\t/* include/uapi/linux/if_link.h */\n\tstruct ifla_vf_broadcast {\n\t\t__u8 broadcast[32];\n\t};\n\nThe function then copies dev-\u003ebroadcast into it using dev-\u003eaddr_len\nas the length:\n\n\tmemcpy(vf_broadcast.broadcast, dev-\u003ebroadcast, dev-\u003eaddr_len);\n\nOn Ethernet devices (the overwhelming majority of SR-IOV NICs)\ndev-\u003eaddr_len is 6, so only the first 6 bytes of broadcast[] are\nwritten. The remaining 26 bytes retain whatever was previously on\nthe kernel stack. The full struct is then handed to userspace via:\n\n\tnla_put(skb, IFLA_VF_BROADCAST,\n\t\tsizeof(vf_broadcast), \u0026vf_broadcast)\n\nleaking up to 26 bytes of uninitialised kernel stack per VF per\nRTM_GETLINK request, repeatable.\n\nThe other vf_* structs in the same function are explicitly zeroed\nfor exactly this reason - see the memset() calls for ivi,\nvf_vlan_info, node_guid and port_guid a few lines above.\nvf_broadcast was simply missed when it was added.\n\nReachability: any unprivileged local process can open AF_NETLINK /\nNETLINK_ROUTE without capabilities and send RTM_GETLINK with an\nIFLA_EXT_MASK attribute carrying RTEXT_FILTER_VF. The kernel walks\neach VF and emits IFLA_VF_BROADCAST, leaking 26 bytes of stack per\nVF per request. Stack residue at this call site can include return\naddresses and transient sensitive data; KASAN with stack\ninstrumentation, or KMSAN, will flag the nla_put() when reproduced.\n\nZero the on-stack struct before the partial memcpy, matching the\nexisting pattern used for the other vf_* structs in the same\nfunction.",
  "id": "GHSA-m5g9-vgm2-5cvw",
  "modified": "2026-05-28T12:30:30Z",
  "published": "2026-05-28T12:30:30Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-46132"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0653c0516234c8258975d268a749115fc0f0ff00"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/38bcc21f52246badb3154b6158dcb381d98de011"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4b9e327991815e128ad3af75c3a04630a63ce3e0"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c5b1b92ab7eff1a6e8c507ddde6fd02fabd0cfa8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/fbe0e6197225e6a83cf113a67a4b425f8de0bcd5"
    }
  ],
  "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-2026-46132 net: rtnetlink: zero ifla_vf_broadcast to avoid stack infoleak in rtnl_fill_vfinfo - VEX",
        "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-46132.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": "net: rtnetlink: zero ifla_vf_broadcast to avoid stack infoleak in rtnl_fill_vfinfo",
    "tracking": {
      "current_release_date": "2026-05-29T01:05:59.000Z",
      "generator": {
        "date": "2026-05-29T07:23:45.802Z",
        "engine": {
          "name": "MSRC Generator",
          "version": "1.0"
        }
      },
      "id": "msrc_CVE-2026-46132",
      "initial_release_date": "2026-05-02T00:00:00.000Z",
      "revision_history": [
        {
          "date": "2026-05-29T01:05:59.000Z",
          "legacy_version": "1",
          "number": "1",
          "summary": "Information published."
        }
      ],
      "status": "final",
      "version": "1"
    }
  },
  "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": "vendor",
        "name": "Microsoft"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-46132",
      "notes": [
        {
          "category": "general",
          "text": "Linux",
          "title": "Assigning CNA"
        }
      ],
      "product_status": {
        "under_investigation": [
          "17084-1"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "CVE-2026-46132 net: rtnetlink: zero ifla_vf_broadcast to avoid stack infoleak in rtnl_fill_vfinfo - VEX",
          "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-46132.json"
        }
      ],
      "title": "net: rtnetlink: zero ifla_vf_broadcast to avoid stack infoleak in rtnl_fill_vfinfo"
    }
  ]
}