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CVE-2026-80760

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: MGMT: reject HCI_CMD_SYNC params_len above 255 mgmt_hci_cmd_sync() checks that the message length agrees with params_len but puts no upper bound on it. params_len is __le16 while the parameter length in the HCI command header is a u8: struct hci_command_hdr { __le16 opcode; __u8 plen; } __packed; hci_cmd_sync_alloc() assigns one to the other: hdr->plen = plen; if (plen) skb_put_data(skb, param, plen); so a params_len of 256 leaves plen at 0 while all 256 bytes are still appended. The frame handed to the driver then declares no parameters and carries 256 of them. On a length framed transport such as H:4 the controller takes the trailing bytes as the start of the next packet. The mgmt socket MTU is HCI_MAX_FRAME_SIZE, so params_len can reach about 1KB this way. Commit 03f1700b9b4d ("Bluetooth: MGMT: reject malformed HCI_CMD_SYNC commands") only made params_len agree with the message length, a value that fits the message but not the header field is still accepted. Reject params_len that does not fit the header field.

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-04 16:18:01.070000
Last modified
2026-10-19 09:17:09.780000
View original CVE JSON
{
  "id": "CVE-2026-80760",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-04T16:18:01.070",
  "lastModified": "2026-10-19T09:17:09.780",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: MGMT: reject HCI_CMD_SYNC params_len above 255\n\nmgmt_hci_cmd_sync() checks that the message length agrees with params_len\nbut puts no upper bound on it. params_len is __le16 while the parameter\nlength in the HCI command header is a u8:\n\n\tstruct hci_command_hdr {\n\t\t__le16\topcode;\n\t\t__u8\tplen;\n\t} __packed;\n\nhci_cmd_sync_alloc() assigns one to the other:\n\n\thdr->plen = plen;\n\n\tif (plen)\n\t\tskb_put_data(skb, param, plen);\n\nso a params_len of 256 leaves plen at 0 while all 256 bytes are still\nappended. The frame handed to the driver then declares no parameters and\ncarries 256 of them. On a length framed transport such as H:4 the\ncontroller takes the trailing bytes as the start of the next packet.\n\nThe mgmt socket MTU is HCI_MAX_FRAME_SIZE, so params_len can reach about\n1KB this way. Commit 03f1700b9b4d (\"Bluetooth: MGMT: reject malformed\nHCI_CMD_SYNC commands\") only made params_len agree with the message\nlength, a value that fits the message but not the header field is still\naccepted.\n\nReject params_len that does not fit the header field."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "net/bluetooth/mgmt.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "827af4787e74e8df9e8e0677a69fbb15e0856d2f",
              "lessThan": "b7d9edcf9fe6e9ec3a2e80ef9e8d44ef9b4f2894",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "827af4787e74e8df9e8e0677a69fbb15e0856d2f",
              "lessThan": "0bd0195ce25737cbdd0eabc54319ee0ddf3a0ad2",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "827af4787e74e8df9e8e0677a69fbb15e0856d2f",
              "lessThan": "6e1c44878aa3ee7336efeaf01414b030b0a5c273",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "827af4787e74e8df9e8e0677a69fbb15e0856d2f",
              "lessThan": "5d95286b6d6e8f1d304da7522bfa6860fc017e48",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "net/bluetooth/mgmt.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.13",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.13",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.47",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1.11",
              "lessThanOrEqual": "7.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.1",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/0bd0195ce25737cbdd0eabc54319ee0ddf3a0ad2",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/5d95286b6d6e8f1d304da7522bfa6860fc017e48",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/6e1c44878aa3ee7336efeaf01414b030b0a5c273",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b7d9edcf9fe6e9ec3a2e80ef9e8d44ef9b4f2894",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}