{"api_version":"1","generated_at":"2026-05-03T12:42:07+00:00","cve":"CVE-2026-31771","urls":{"html":"https://cve.report/CVE-2026-31771","api":"https://cve.report/api/cve/CVE-2026-31771.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-31771","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-31771"},"summary":{"title":"Bluetooth: hci_event: move wake reason storage into validated event handlers","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: hci_event: move wake reason storage into validated event handlers\n\nhci_store_wake_reason() is called from hci_event_packet() immediately\nafter stripping the HCI event header but before hci_event_func()\nenforces the per-event minimum payload length from hci_ev_table.\nThis means a short HCI event frame can reach bacpy() before any bounds\ncheck runs.\n\nRather than duplicating skb parsing and per-event length checks inside\nhci_store_wake_reason(), move wake-address storage into the individual\nevent handlers after their existing event-length validation has\nsucceeded. Convert hci_store_wake_reason() into a small helper that only\nstores an already-validated bdaddr while the caller holds hci_dev_lock().\nUse the same helper after hci_event_func() with a NULL address to\npreserve the existing unexpected-wake fallback semantics when no\nvalidated event handler records a wake address.\n\nAnnotate the helper with __must_hold(&hdev->lock) and add\nlockdep_assert_held(&hdev->lock) so future call paths keep the lock\ncontract explicit.\n\nCall the helper from hci_conn_request_evt(), hci_conn_complete_evt(),\nhci_sync_conn_complete_evt(), le_conn_complete_evt(),\nhci_le_adv_report_evt(), hci_le_ext_adv_report_evt(),\nhci_le_direct_adv_report_evt(), hci_le_pa_sync_established_evt(), and\nhci_le_past_received_evt().","state":"PUBLISHED","assigner":"Linux","published_at":"2026-05-01 15:16:40","updated_at":"2026-05-03 07:16:20"},"problem_types":[],"metrics":[{"version":"3.1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","score":"8.1","severity":"HIGH","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","baseScore":8.1,"baseSeverity":"HIGH","attackVector":"ADJACENT_NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"NONE","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"8.1","severity":"HIGH","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","data":{"baseScore":8.1,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","version":"3.1"}}],"references":[{"url":"https://git.kernel.org/stable/c/86c8d07a64d553c41e213b52650020010f9ef23e","name":"https://git.kernel.org/stable/c/86c8d07a64d553c41e213b52650020010f9ef23e","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/2b2bf47cd75518c36fa2d41380e4a40641cc89cd","name":"https://git.kernel.org/stable/c/2b2bf47cd75518c36fa2d41380e4a40641cc89cd","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-31771","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-31771","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2f20216c1d6fe17c1a224f658be0dc6fab2269c7 86c8d07a64d553c41e213b52650020010f9ef23e git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2f20216c1d6fe17c1a224f658be0dc6fab2269c7 2b2bf47cd75518c36fa2d41380e4a40641cc89cd git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.10","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.10 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.19.12 6.19.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"31771","cve":"CVE-2026-31771","epss":"0.000210000","percentile":"0.059300000","score_date":"2026-05-02","updated_at":"2026-05-03 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the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: hci_event: move wake reason storage into validated event handlers\n\nhci_store_wake_reason() is called from hci_event_packet() immediately\nafter stripping the HCI event header but before hci_event_func()\nenforces the per-event minimum payload length from hci_ev_table.\nThis means a short HCI event frame can reach bacpy() before any bounds\ncheck runs.\n\nRather than duplicating skb parsing and per-event length checks inside\nhci_store_wake_reason(), move wake-address storage into the individual\nevent handlers after their existing event-length validation has\nsucceeded. Convert hci_store_wake_reason() into a small helper that only\nstores an already-validated bdaddr while the caller holds hci_dev_lock().\nUse the same helper after hci_event_func() with a NULL address to\npreserve the existing unexpected-wake fallback semantics when no\nvalidated event handler records a wake address.\n\nAnnotate the helper with __must_hold(&hdev->lock) and add\nlockdep_assert_held(&hdev->lock) so future call paths keep the lock\ncontract explicit.\n\nCall the helper from hci_conn_request_evt(), hci_conn_complete_evt(),\nhci_sync_conn_complete_evt(), le_conn_complete_evt(),\nhci_le_adv_report_evt(), hci_le_ext_adv_report_evt(),\nhci_le_direct_adv_report_evt(), hci_le_pa_sync_established_evt(), and\nhci_le_past_received_evt()."}],"metrics":[{"cvssV3_1":{"baseScore":8.1,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","version":"3.1"}}],"providerMetadata":{"dateUpdated":"2026-05-03T05:45:51.711Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/86c8d07a64d553c41e213b52650020010f9ef23e"},{"url":"https://git.kernel.org/stable/c/2b2bf47cd75518c36fa2d41380e4a40641cc89cd"}],"title":"Bluetooth: hci_event: move wake reason storage into validated event handlers","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-31771","datePublished":"2026-05-01T14:14:59.918Z","dateReserved":"2026-03-09T15:48:24.140Z","dateUpdated":"2026-05-03T05:45:51.711Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-05-01 15:16:40","lastModifiedDate":"2026-05-03 07:16:20","problem_types":[],"metrics":{"cvssMetricV31":[{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","baseScore":8.1,"baseSeverity":"HIGH","attackVector":"ADJACENT_NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":2.8,"impactScore":5.2}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"31771","Ordinal":"1","Title":"Bluetooth: hci_event: move wake reason storage into validated ev","CVE":"CVE-2026-31771","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"31771","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: hci_event: move wake reason storage into validated event handlers\n\nhci_store_wake_reason() is called from hci_event_packet() immediately\nafter stripping the HCI event header but before hci_event_func()\nenforces the per-event minimum payload length from hci_ev_table.\nThis means a short HCI event frame can reach bacpy() before any bounds\ncheck runs.\n\nRather than duplicating skb parsing and per-event length checks inside\nhci_store_wake_reason(), move wake-address storage into the individual\nevent handlers after their existing event-length validation has\nsucceeded. Convert hci_store_wake_reason() into a small helper that only\nstores an already-validated bdaddr while the caller holds hci_dev_lock().\nUse the same helper after hci_event_func() with a NULL address to\npreserve the existing unexpected-wake fallback semantics when no\nvalidated event handler records a wake address.\n\nAnnotate the helper with __must_hold(&hdev->lock) and add\nlockdep_assert_held(&hdev->lock) so future call paths keep the lock\ncontract explicit.\n\nCall the helper from hci_conn_request_evt(), hci_conn_complete_evt(),\nhci_sync_conn_complete_evt(), le_conn_complete_evt(),\nhci_le_adv_report_evt(), hci_le_ext_adv_report_evt(),\nhci_le_direct_adv_report_evt(), hci_le_pa_sync_established_evt(), and\nhci_le_past_received_evt().","Type":"Description","Title":"Bluetooth: hci_event: move wake reason storage into validated ev"}]}}}