{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-63974", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T07:54:57.024Z", "datePublished": "2026-07-19T14:55:59.994Z", "dateUpdated": "2026-08-05T12:37:44.929Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:37:44.929Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: hci_sync: Set HCI_CMD_DRAIN_WORKQUEUE during device close\n\nSince hci_dev_close_sync() can now be called during the reset path, we\nshould also set HCI_CMD_DRAIN_WORKQUEUE. This avoids queuing timeouts\nwhile the hdev workqueue is being drained." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:A - This is a Bluetooth HCI subsystem bug where exploitation requires concurrent HCI controller events from the radio during adapter close/reset; on phones and laptops with Bluetooth enabled in public spaces, a nearby attacker can supply that traffic while the kernel tears down the adapter.\nAC:L - The attacker controls both sides of the race by timing Bluetooth traffic against adapter reset/close or error-recovery teardown, and syzbot reliably reproduced the original workqueue-drain class of this bug.\nPR:N - No local credentials are required on the remote path: a nearby Bluetooth attacker can drive ncmd/cmd timeout recovery that calls hci_dev_do_close() → hci_dev_close_sync(); local CAP_NET_ADMIN ioctl reset is an additional reachable path via user namespaces.\nUI:N - Exploitation does not require the victim to perform a specific action beyond having Bluetooth enabled, which is the default on most mobile and laptop deployments.\nS:U - Impact is confined to kernel Bluetooth/HCI state and does not cross a security boundary such as a VM escape or sandbox breakout.\nC:H - Queueing work onto a draining workqueue corrupts kernel workqueue metadata for cmd_timer/ncmd_timer delayed-work structures, which is memory corruption that could be leveraged for information disclosure during the close/open reset cycle.\nI:H - The workqueue invariant violation leaves delayed-work items in inconsistent states on a persistent hdev->workqueue that is reused after reset, creating a plausible path to control-flow hijack via corrupted work callbacks.\nA:H - Triggering this bug produces a kernel WARNING in __queue_work() (kernel panic on panic_on_warn systems) and can cause drain_workqueue() to spin with repeated reflush attempts, denying Bluetooth availability and potentially hanging the adapter teardown path." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/bluetooth/hci_sync.c" ], "versions": [ { "version": "877afadad2dce8aae1f2aad8ce47e072d4f6165e", "lessThan": "9cebe4680bb9a72f80c6541eb24af06db7a1fbc9", "status": "affected", "versionType": "git" }, { "version": "877afadad2dce8aae1f2aad8ce47e072d4f6165e", "lessThan": "47330cc875b36a1cf7b3543cb2cf90a7c603ce0e", "status": "affected", "versionType": "git" }, { "version": "877afadad2dce8aae1f2aad8ce47e072d4f6165e", "lessThan": "60bceb9a4c693e68cc90ba4b2dfb9e000e8638ff", "status": "affected", "versionType": "git" }, { "version": "877afadad2dce8aae1f2aad8ce47e072d4f6165e", "lessThan": "525daaea459fc215f432de1b8debbd9144bf97b0", "status": "affected", "versionType": "git" }, { "version": "4bf367fa1fefabdf14938d0ac9ed60020389112e", "status": "affected", "versionType": "git" }, { "version": "3b382555706558f5c0587862b6dc03e96a252bba", "status": "affected", "versionType": "git" }, { "version": "5.18.18", "lessThan": "5.19", "status": "affected", "versionType": "semver" }, { "version": "5.19.2", "lessThan": "5.20", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/bluetooth/hci_sync.c" ], "versions": [ { "version": "6.0", "status": "affected" }, { "version": "0", "lessThan": "6.0", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.93", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.35", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0.12", "lessThanOrEqual": "7.0.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "6.12.93" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "6.18.35" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "7.0.12" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "7.1" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.18.18" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.19.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/9cebe4680bb9a72f80c6541eb24af06db7a1fbc9" }, { "url": "https://git.kernel.org/stable/c/47330cc875b36a1cf7b3543cb2cf90a7c603ce0e" }, { "url": "https://git.kernel.org/stable/c/60bceb9a4c693e68cc90ba4b2dfb9e000e8638ff" }, { "url": "https://git.kernel.org/stable/c/525daaea459fc215f432de1b8debbd9144bf97b0" } ], "title": "Bluetooth: hci_sync: Set HCI_CMD_DRAIN_WORKQUEUE during device close", "x_generator": { "engine": "bippy-1.2.0" } } } }