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CVE-2026-23395

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix accepting multiple L2CAP_ECRED_CONN_REQ Currently the code attempts to accept requests regardless of the command identifier which may cause multiple requests to be marked as pending (FLAG_DEFER_SETUP) which can cause more than L2CAP_ECRED_MAX_CID(5) to be allocated in l2cap_ecred_rsp_defer causing an overflow. The spec is quite clear that the same identifier shall not be used on subsequent requests: 'Within each signaling channel a different Identifier shall be used for each successive request or indication.' https://www.bluetooth.com/wp-content/uploads/Files/Specification/HTML/Core-62/out/en/host/logical-link-control-and-adaptation-protocol-specification.html#UUID-32a25a06-4aa4-c6c7-77c5-dcfe3682355d So this attempts to check if there are any channels pending with the same identifier and rejects if any are found.

Severity
HIGH
CVSS score
8.8 (v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-03-25 11:16:40.347000
Last modified
2026-10-19 19:17:46.807000
View original CVE JSON
{
  "id": "CVE-2026-23395",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-03-25T11:16:40.347",
  "lastModified": "2026-10-19T19:17:46.807",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: Fix accepting multiple L2CAP_ECRED_CONN_REQ\n\nCurrently the code attempts to accept requests regardless of the\ncommand identifier which may cause multiple requests to be marked\nas pending (FLAG_DEFER_SETUP) which can cause more than\nL2CAP_ECRED_MAX_CID(5) to be allocated in l2cap_ecred_rsp_defer\ncausing an overflow.\n\nThe spec is quite clear that the same identifier shall not be used on\nsubsequent requests:\n\n'Within each signaling channel a different Identifier shall be used\nfor each successive request or indication.'\nhttps://www.bluetooth.com/wp-content/uploads/Files/Specification/HTML/Core-62/out/en/host/logical-link-control-and-adaptation-protocol-specification.html#UUID-32a25a06-4aa4-c6c7-77c5-dcfe3682355d\n\nSo this attempts to check if there are any channels pending with the\nsame identifier and rejects if any are found."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nBluetooth: L2CAP: Corrección para aceptar múltiples L2CAP_ECRED_CONN_REQ\n\nActualmente, el código intenta aceptar solicitudes independientemente del identificador de comando, lo que puede hacer que múltiples solicitudes se marquen como pendientes (FLAG_DEFER_SETUP), lo que puede causar que se asignen más de L2CAP_ECRED_MAX_CID(5) en l2cap_ecred_rsp_defer, causando un desbordamiento.\n\nLa especificación es bastante clara en que el mismo identificador no debe usarse en solicitudes subsiguientes:\n\n'Dentro de cada canal de señalización se utilizará un identificador diferente para cada solicitud o indicación sucesiva.'\nhttps://www.bluetooth.com/wp-content/uploads/Files/Specification/HTML/Core-62/out/en/host/logical-link-control-and-adaptation-protocol-specification.html#UUID-32a25a06-4aa4-c6c7-77c5-dcfe3682355d\n\nAsí que esto intenta verificar si hay canales pendientes con el mismo identificador y los rechaza si se encuentra alguno."
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