{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-68393", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-30T09:28:09.388Z", "datePublished": "2026-08-10T12:04:12.564Z", "dateUpdated": "2026-08-17T05:04:41.234Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T05:04:41.234Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: hci_sync: extend conn_hash lookup critical sections\n\nUsing RCU-protected pointers outside the critical sections without\nrefcount is incorrect and may result to UAF.\n\nExtend critical section to cover both hci_conn_hash lookup and use of\nthe returned conn.\n\nAdd surrounding rcu_read_lock() also when return value is not used, in\npreparation for RCU lockdep requirement to hci_lookup_le_connect().\n\nThis avoids concurrent deletion of the conn before we are done\ndereferencing it.\n\nAlso, make sure to hold hdev->lock when accessing hdev->accept_list." } ], "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 - The affected code is the Bluetooth HCI sync/scan management layer; both sides of the race are driven by LE radio events (connection complete, disconnect, periodic advertising sync creation/termination) from a device in radio range, requiring no local access.\nAC:L - A nearby attacker drives both sides of the race — repeated LE connect/disconnect and PA sync setup/teardown queue the hci_sync work while concurrently triggering hci_conn_del() on the event workqueue — so the window can be re-attempted arbitrarily until won.\nPR:N - The vulnerable hci_update_passive_scan_sync()/hci_update_accept_list_sync()/hci_le_set_ext_scan_param_sync() paths are invoked automatically by the kernel in response to incoming LE connection and periodic-advertising events; the remote attacker needs no credentials or pairing on the target.\nUI:N - No victim action is needed — background LE scanning and accept-list updates are performed autonomously by the host stack whenever connection state changes.\nS:U - The use-after-free occurs in kernel memory and its impact is confined to the kernel's own security authority, with no crossing into a separate authorization scope such as a hypervisor or IOMMU boundary.\nC:H - The freed hci_conn is read after release (conn->dst, conn->dst_type, PHY parameters), and a heap-groomed replacement object lets the attacker read attacker-chosen or sensitive kernel data, which can additionally be exfiltrated via the resulting accept-list/scan parameters.\nI:H - hci_conn is kfree()'d via bt_link_release() while still referenced, so reallocating the slab with a controlled object yields write/control-flow primitives typical of slab use-after-free, enabling kernel memory corruption and privilege escalation.\nA:H - Dereferencing the freed hci_conn readily causes slab corruption, KASAN splats, or an oops/panic in the Bluetooth workqueues, taking down the kernel." } ] } ], "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": "6d0417e4e1cf66fd917f06f0454958362714ef7d", "lessThan": "83b7e67698d0b93f685875ce82c8d335436834f7", "status": "affected", "versionType": "git" }, { "version": "6d0417e4e1cf66fd917f06f0454958362714ef7d", "lessThan": "38326774df6198df0cc2744cc73bf77cb741c538", "status": "affected", "versionType": "git" }, { "version": "6d0417e4e1cf66fd917f06f0454958362714ef7d", "lessThan": "d5efd6e4b8b0634af6843178fe1a7dd2b2178a3d", "status": "affected", "versionType": "git" }, { "version": "eb8b860e87b296bd1874c79a668081efd00f9754", "status": "affected", "versionType": "git" }, { "version": "94bf6380e936339a700c0b3171a49baf512aa70b", "status": "affected", "versionType": "git" }, { "version": "6.12.28", "lessThan": "6.13", "status": "affected", "versionType": "semver" }, { "version": "6.14.6", "lessThan": "6.15", "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": "6.15", "status": "affected" }, { "version": "0", "lessThan": "6.15", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.42", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.6", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "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": "6.15", "versionEndExcluding": "6.18.42" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.15", "versionEndExcluding": "7.1.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.15", "versionEndExcluding": "7.2" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12.28" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.14.6" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/83b7e67698d0b93f685875ce82c8d335436834f7" }, { "url": "https://git.kernel.org/stable/c/38326774df6198df0cc2744cc73bf77cb741c538" }, { "url": "https://git.kernel.org/stable/c/d5efd6e4b8b0634af6843178fe1a7dd2b2178a3d" } ], "title": "Bluetooth: hci_sync: extend conn_hash lookup critical sections", "x_generator": { "engine": "bippy-1.2.0" } } } }