boxscore/security
CVE · referencelatest edition

Reference page — cumulative record through Sunday, October 4, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-64405

Linux Linux — Bluetooth: hci_conn: Fix null ptr deref in hci_abort_conn()
  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   L   L   L   N  U  N  N  H    5.5   .0016    4.3     —
AFFECTED
  Product  Versions                                    Fixed
  Linux    6083089ab00631617f9eac678df3ab050a9d837a –  —
  Linux    6.6 –                                       6.1.118
TIMELINE
  Jul 19  Reserved by Linux
  Jul 25  Published (CNA: Linux)
  Sep 4   ENRICHED — CVE-2026-64405 (Linux). Received CVSS 5.5 and CPE data from NVD.
CWE-476 · CNA: Linux · CVSS v3.1 · 6 references · NVD status: Analyzed

Description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_conn: Fix null ptr deref in hci_abort_conn() hci_abort_conn() read hci_skb_event(hdev->sent_cmd) when a connection was pending, but hdev->sent_cmd can be NULL while req_status is still HCI_REQ_PEND, leading to a NULL pointer dereference and a general protection fault from the hci_rx_work() receive path. Instead of inspecting hdev->sent_cmd, track the in-flight create connection command with a new per-connection HCI_CONN_CREATE flag and route all cancellation through hci_cancel_connect_sync(), which dispatches to a dedicated per-type cancel function. The create command is in exactly one of two states: still queued, or in flight. The cancel function holds cmd_sync_work_lock across the whole decision: the worker takes this lock to dequeue every entry, so while it is held a queued command cannot start running and an in-flight command cannot complete and let the next command become pending. This keeps the flag test and hci_cmd_sync_cancel() atomic with respect to the worker, so a queued command is simply dequeued, and an in-flight command owned by this connection is cancelled without the risk of cancelling an unrelated command that became pending in the meantime. CIS uses the same flag mechanism via HCI_CONN_CREATE_CIS but cannot be dequeued per-connection. hci_acl_create_conn_sync() and hci_le_create_conn_sync() clear HCI_CONN_CREATE after the create command completes, but the command status handler can free conn via hci_conn_del() (for example when the controller rejects the connection) while the worker is still blocked on the connection complete event. Hold a reference on conn across the create command so the flag can be cleared without a use-after-free.

Lifecycle

Complete event history — 3 events, chronological
DateEventDetail
July 19, 2026ReservedReserved by Linux
July 25, 2026PublishedPublished (CNA: Linux)
September 4, 2026ENRICHEDENRICHED — CVE-2026-64405 (Linux). Received CVSS 5.5 and CPE data from NVD.

Affected

Affected products and packages — 2 rows
VendorProduct / PackageEcosystemVersion introducedFixed
LinuxLinux—6083089ab00631617f9eac678df3ab050a9d837a—
LinuxLinux—6.66.1.118

Weaknesses

CWE-476

References (6)

Related

Authoritative record: CVE-2026-64405 at cve.org

Vendors: linux

Weaknesses: CWE-476

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-64405 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Sunday, October 4, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.