CVE-2026-10660

{
  "id": "CVE-2026-10660",
  "sourceIdentifier": "[email protected]",
  "published": "2026-07-11T17:16:23.920",
  "lastModified": "2026-10-25T15:10:00.147",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "The Bluetooth BAP Broadcast Assistant GATT client in subsys/bluetooth/audio/bap_broadcast_assistant.c reassembled remote Broadcast Receive State data into a single file-static net_buf_simple (att_buf, BT_ATT_MAX_ATTRIBUTE_LEN = 512 bytes) shared by all connection instances, while the BUSY flag, long-read handle, and reset/offset state were per-connection.\n\nWhen the device acts as a Broadcast Assistant connected to multiple Scan Delegator peripherals, notification and long-read callbacks from different connections interleave on the shared buffer: the append in notify_handler (net_buf_simple_add_mem at the not-busy branch) performs no tailroom check, so receive-state notifications from two or more delegators accumulate on the same 512-byte buffer and, with a sufficiently large configured ATT MTU (BT_L2CAP_TX_MTU up to 2000) and two-to-three concurrent connections, write past the buffer into adjacent .bss (net_buf_simple_add only asserts in debug builds).\n\nEven below the overflow threshold, one connection's net_buf_simple_reset zeroes the shared length while another connection's reassembly and GATT read offset are in flight, mixing one peer's data into another's parse. A malicious or compromised Scan Delegator (or two colluding peers) over BLE can trigger this, causing out-of-bounds writes (memory corruption / denial of service) and cross-connection data corruption.\n\nThe fix moves the buffer into the per-connection instance struct so each connection reassembles into its own buffer. Affects Zephyr releases shipping the Broadcast Assistant with the shared buffer, including v4.4.0 and earlier."
    },
    {
      "lang": "es",
      "value": "El cliente GATT Bluetooth BAP Broadcast Assistant en subsys/bluetooth/audio/bap_broadcast_assistant.c reensambló datos remotos de Broadcast Receive State en un único net_buf_simple estático de archivo (att_buf, BT_ATT_MAX_ATTRIBUTE_LEN = 512 bytes) compartido por todas las instancias de conexión, mientras que el indicador BUSY, el manejador de lectura larga y el estado de reinicio/desplazamiento eran por conexión.\n\nCuando el dispositivo actúa como un Broadcast Assistant conectado a múltiples periféricos Scan Delegator, las devoluciones de llamada de notificación y lectura larga de diferentes conexiones se entrelazan en el búfer compartido: la adición en notify_handler (net_buf_simple_add_mem en la rama no ocupada) no realiza ninguna comprobación de espacio restante, por lo que las notificaciones de estado de recepción de dos o más delegadores se acumulan en el mismo búfer de 512 bytes y, con una MTU ATT configurada suficientemente grande (BT_L2CAP_TX_MTU hasta 2000) y de dos a tres conexiones concurrentes, escriben más allá del búfer en el .bss adyacente (net_buf_simple_add solo se afirma en compilaciones de depuración).\n\nIncluso por debajo del umbral de desbordamiento, el net_buf_simple_reset de una conexión pone a cero la longitud compartida mientras que el reensamblaje y el desplazamiento de lectura GATT de otra conexión están en curso, mezclando los datos de un par en el análisis de otro. Un Scan Delegator malicioso o comprometido (o dos pares en colusión) a través de BLE puede desencadenar esto, causando escrituras fuera de límites (corrupción de memoria / denegación de servicio) y corrupción de datos entre conexiones.\n\nLa solución mueve el búfer a la estructura de instancia por conexión para que cada conexión reensamble en su propio búfer. Afecta a las versiones de Zephyr que distribuyen el Broadcast Assistant con el búfer compartido, incluyendo la v4.4.0 y anteriores."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "zephyrproject",
          "product": "zephyr",
          "defaultStatus": "unaffected",
          "collectionURL": "https://github.com/zephyrproject-rtos/zephyr",
          "packageName": "zephyr",
          "programFiles": [
            "subsys/bluetooth/audio/bap_broadcast_assistant.c"
          ],
          "versions": [
            {
              "version": "3.6.0",
              "lessThan": "4.3.1",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "4.4.0",
              "lessThan": "4.4.2",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H",
          "baseScore": 6.4,
          "baseSeverity": "MEDIUM",
          "attackVector": "ADJACENT_NETWORK",
          "attackComplexity": "HIGH",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.6,
        "impactScore": 4.7
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-07-13T15:44:09.257224Z",
          "id": "CVE-2026-10660",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-787"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/zephyrproject-rtos/zephyr/commit/0cd61589ff820b6a585c73cb36f1e14b043a2795",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-73c7-3rh7-v5p9",
      "source": "[email protected]"
    }
  ]
}