CVE-2026-23395
kernel: Bluetooth: L2CAP: Fix accepting multiple L2CAP_ECRED_CONN_REQ
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · March 25, 2026
Updated · July 3, 2026
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.
Statement
This vulnerability is rated as Moderate. Successfully triggering this bug can result in memory corruption if the overflow overwrites adjacent kernel structures, though it most likely will result in a DoS due to a kernel panic.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 6.3CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H
CWE-190 · Integer Overflow or Wraparound