wifi: brcmfmac: cyw: fix heap overflow on a short auth frame

{
  "id": "9cc634e88b3e0dab643d2f085cb0aa4fc8b18b36d519cf1831fe9952a1b61ac3",
  "url": "https://osv.dev/vulnerability/CVE-2026-72003",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "wifi: brcmfmac: cyw: fix heap overflow on a short auth frame",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: wifi: brcmfmac: cyw: fix heap overflow on a short auth frame brcmf_notify_auth_frame_rx() takes the frame length from the firmware event and copies the frame body with the management header offset subtracted: u32 mgmt_frame_len = e->datalen - sizeof(struct brcmf_rx_mgmt_data); ... memcpy(&mgmt_frame->u, frame, mgmt_frame_len - offsetof(struct ieee80211_mgmt, u)); The only length check is e->datalen >= sizeof(*rxframe), so mgmt_frame_len can be anything from 0 up. offsetof(struct ieee80211_mgmt, u) is 24. When mgmt_frame_len is below that, the subtraction wraps as an unsigned value to a huge length. The memcpy then runs far past the kzalloc'd buffer. A malicious or malfunctioning AP can make the frame short during the external SAE auth exchange, so this is a remotely triggered heap overflow. Reject frames shorter than the management header offset before the copy.",
    "evidence": "osv:CVE-2026-72003",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.18.40",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.1.5",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-72003",
      "aliases": [
        "CVE-2026-72003"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
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              "type": "GIT",
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                {
                  "fixed": "185bb156c427d0f865d344a6d0eaa02c6d05cc57"
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                  "fixed": "240c8d2c717b3f8153e7e877b22a82518d78dbdc"
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          "database_specific": {
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        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.16.0"
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                {
                  "fixed": "6.18.40"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
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                {
                  "fixed": "7.1.5"
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          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
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          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-72003.json"
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      ],
      "modified": "2026-10-28T02:30:29.698198384Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/185bb156c427d0f865d344a6d0eaa02c6d05cc57",
        "https://git.kernel.org/stable/c/240c8d2c717b3f8153e7e877b22a82518d78dbdc",
        "https://git.kernel.org/stable/c/55b26abb1fa1ec406b3ad11b43c49c7624257565",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72003.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-72003",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72003.json"
      }
    },
    "related_cves": [
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        "value": "CVE-2026-72003",
        "evidence": "/id"
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    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 496752,
  "published_at": "2026-08-15T05:51:34.73+00:00"
}