Bluetooth: hci_event: move wake reason storage into validated event handlers
Summary
| CVE | CVE-2026-31771 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-05-01 15:16:40 UTC |
| Updated | 2026-05-03 07:16:20 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_event: move wake reason storage into validated event handlers hci_store_wake_reason() is called from hci_event_packet() immediately after stripping the HCI event header but before hci_event_func() enforces the per-event minimum payload length from hci_ev_table. This means a short HCI event frame can reach bacpy() before any bounds check runs. Rather than duplicating skb parsing and per-event length checks inside hci_store_wake_reason(), move wake-address storage into the individual event handlers after their existing event-length validation has succeeded. Convert hci_store_wake_reason() into a small helper that only stores an already-validated bdaddr while the caller holds hci_dev_lock(). Use the same helper after hci_event_func() with a NULL address to preserve the existing unexpected-wake fallback semantics when no validated event handler records a wake address. Annotate the helper with __must_hold(&hdev->lock) and add lockdep_assert_held(&hdev->lock) so future call paths keep the lock contract explicit. Call the helper from hci_conn_request_evt(), hci_conn_complete_evt(), hci_sync_conn_complete_evt(), le_conn_complete_evt(), hci_le_adv_report_evt(), hci_le_ext_adv_report_evt(), hci_le_direct_adv_report_evt(), hci_le_pa_sync_established_evt(), and hci_le_past_received_evt(). |
Risk And Classification
Primary CVSS: v3.1 8.1 HIGH from 416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
EPSS: 0.000210000 probability, percentile 0.059300000 (date 2026-05-02)
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | Secondary | 8.1 | HIGH | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H |
| 3.1 | CNA | DECLARED | 8.1 | HIGH | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H |
CVSS v3.1 Breakdown
Attack Vector
AdjacentAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
NoneAvailability
HighCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected 2f20216c1d6fe17c1a224f658be0dc6fab2269c7 86c8d07a64d553c41e213b52650020010f9ef23e git | Not specified |
| CNA | Linux | Linux | affected 2f20216c1d6fe17c1a224f658be0dc6fab2269c7 2b2bf47cd75518c36fa2d41380e4a40641cc89cd git | Not specified |
| CNA | Linux | Linux | affected 5.10 | Not specified |
| CNA | Linux | Linux | unaffected 5.10 semver | Not specified |
| CNA | Linux | Linux | unaffected 6.19.12 6.19.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.0 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/86c8d07a64d553c41e213b52650020010f9ef23e | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/2b2bf47cd75518c36fa2d41380e4a40641cc89cd | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.