{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2023-53762", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-12-08T01:18:04.281Z", "datePublished": "2025-12-08T01:19:23.927Z", "dateUpdated": "2026-08-05T09:15:52.195Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T09:15:52.195Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: hci_sync: Fix UAF in hci_disconnect_all_sync\n\nUse-after-free can occur in hci_disconnect_all_sync if a connection is\ndeleted by concurrent processing of a controller event.\n\nTo prevent this the code now tries to iterate over the list backwards\nto ensure the links are cleanup before its parents, also it no longer\nrelies on a cursor, instead it always uses the last element since\nhci_abort_conn_sync is guaranteed to call hci_conn_del.\n\nUAF crash log:\n==================================================================\nBUG: KASAN: slab-use-after-free in hci_set_powered_sync\n(net/bluetooth/hci_sync.c:5424) [bluetooth]\nRead of size 8 at addr ffff888009d9c000 by task kworker/u9:0/124\n\nCPU: 0 PID: 124 Comm: kworker/u9:0 Tainted: G W\n6.5.0-rc1+ #10\nHardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS\n1.16.2-1.fc38 04/01/2014\nWorkqueue: hci0 hci_cmd_sync_work [bluetooth]\nCall Trace:\n \n dump_stack_lvl+0x5b/0x90\n print_report+0xcf/0x670\n ? __virt_addr_valid+0xdd/0x160\n ? hci_set_powered_sync+0x2c9/0x4a0 [bluetooth]\n kasan_report+0xa6/0xe0\n ? hci_set_powered_sync+0x2c9/0x4a0 [bluetooth]\n ? __pfx_set_powered_sync+0x10/0x10 [bluetooth]\n hci_set_powered_sync+0x2c9/0x4a0 [bluetooth]\n ? __pfx_hci_set_powered_sync+0x10/0x10 [bluetooth]\n ? __pfx_lock_release+0x10/0x10\n ? __pfx_set_powered_sync+0x10/0x10 [bluetooth]\n hci_cmd_sync_work+0x137/0x220 [bluetooth]\n process_one_work+0x526/0x9d0\n ? __pfx_process_one_work+0x10/0x10\n ? __pfx_do_raw_spin_lock+0x10/0x10\n ? mark_held_locks+0x1a/0x90\n worker_thread+0x92/0x630\n ? __pfx_worker_thread+0x10/0x10\n kthread+0x196/0x1e0\n ? __pfx_kthread+0x10/0x10\n ret_from_fork+0x2c/0x50\n \n\nAllocated by task 1782:\n kasan_save_stack+0x33/0x60\n kasan_set_track+0x25/0x30\n __kasan_kmalloc+0x8f/0xa0\n hci_conn_add+0xa5/0xa80 [bluetooth]\n hci_bind_cis+0x881/0x9b0 [bluetooth]\n iso_connect_cis+0x121/0x520 [bluetooth]\n iso_sock_connect+0x3f6/0x790 [bluetooth]\n __sys_connect+0x109/0x130\n __x64_sys_connect+0x40/0x50\n do_syscall_64+0x60/0x90\n entry_SYSCALL_64_after_hwframe+0x6e/0xd8\n\nFreed by task 695:\n kasan_save_stack+0x33/0x60\n kasan_set_track+0x25/0x30\n kasan_save_free_info+0x2b/0x50\n __kasan_slab_free+0x10a/0x180\n __kmem_cache_free+0x14d/0x2e0\n device_release+0x5d/0xf0\n kobject_put+0xdf/0x270\n hci_disconn_complete_evt+0x274/0x3a0 [bluetooth]\n hci_event_packet+0x579/0x7e0 [bluetooth]\n hci_rx_work+0x287/0xaa0 [bluetooth]\n process_one_work+0x526/0x9d0\n worker_thread+0x92/0x630\n kthread+0x196/0x1e0\n ret_from_fork+0x2c/0x50\n==================================================================" } ], "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 freeing side of the race is `hci_disconn_complete_evt()` processed from HCI events generated by a peer Bluetooth device terminating a link or causing link-supervision timeout, so the attacker must be a device within Bluetooth radio range. Bluetooth reachability is scored Adjacent.\nAC:L - The attacker controls the free side entirely (link teardown timing and the multi-link ACL/SCO or LE/CIS topology that makes `hci_conn_unlink()` cascade a `hci_conn_del()` onto the loop's cached cursor), and the window is wide because `hci_disconnect_sync()` sleeps on `HCI_CMD_TIMEOUT` without waiting for Disconnect Complete. The victim-side trigger (adapter power-off or the routine autosuspend path via `hci_suspend_sync()`) recurs constantly, and attempts can be retried indefinitely.\nPR:N - The attacker needs no account, capability, or credential on the target host — only an in-range Bluetooth link, which for LE/L2CAP/CIS can be established without pairing. No local privilege on the victim is required to deliver the disconnect that frees the `hci_conn`.\nUI:N - `hci_disconnect_all_sync()` is reached automatically by `hci_suspend_sync()` on every system/auto suspend that has active connections, and by rfkill/adapter power-down performed by system daemons. No deliberate victim action is needed.\nS:U - The corruption stays within the kernel's own security authority; there is no crossing into a hypervisor, IOMMU, or other separate security scope.\nC:H - The freed `hci_conn` is read after free (`conn->state`, `conn->handle`, `conn->type`, `conn->dst`) from a sprayable general kmalloc cache, letting an attacker who reallocates the slot both leak kernel memory contents and steer subsequent reads for arbitrary disclosure.\nI:H - The dangling object is passed on to `hci_conn_failed()`/`hci_conn_del()`, which performs `list_del` on attacker-controlled list pointers (write primitive) and calls the `conn->cleanup(conn)` function pointer out of freed memory in `hci_conn_cleanup()`, giving control-flow hijack and privilege escalation potential.\nA:H - The confirmed KASAN slab-use-after-free in the `hci_cmd_sync_work` kernel worker crashes the kernel, and it can be re-triggered on every power-off/suspend cycle for persistent denial of service." } ] } ], "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": "182ee45da083db4e3e621541ccf255bfa9652214", "lessThan": "a30c074f0b5b7f909a15c978fbc96a29e2f94e42", "status": "affected", "versionType": "git" }, { "version": "182ee45da083db4e3e621541ccf255bfa9652214", "lessThan": "ba3ba53ce1f76fc372b8f918fece4f9b1e41acd4", "status": "affected", "versionType": "git" }, { "version": "182ee45da083db4e3e621541ccf255bfa9652214", "lessThan": "94d9ba9f9888b748d4abd2aa1547af56ae85f772", "status": "affected", "versionType": "git" } ] }, { "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": "5.17", "status": "affected" }, { "version": "0", "lessThan": "5.17", "status": "unaffected", "versionType": "semver" }, { "version": "6.4.16", "lessThanOrEqual": "6.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.5.3", "lessThanOrEqual": "6.5.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6", "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": "5.17", "versionEndExcluding": "6.4.16" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.17", "versionEndExcluding": "6.5.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.17", "versionEndExcluding": "6.6" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/a30c074f0b5b7f909a15c978fbc96a29e2f94e42" }, { "url": "https://git.kernel.org/stable/c/ba3ba53ce1f76fc372b8f918fece4f9b1e41acd4" }, { "url": "https://git.kernel.org/stable/c/94d9ba9f9888b748d4abd2aa1547af56ae85f772" } ], "title": "Bluetooth: hci_sync: Fix UAF in hci_disconnect_all_sync", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "timestamp": "2026-06-16T15:46:42.482426Z", "id": "CVE-2023-53762", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "role": "CISA Coordinator", "version": "2.0.3" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-06-16T15:47:51.661Z" } } ] } }