{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-40318", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T07:20:57.186Z", "datePublished": "2025-12-08T00:46:45.382Z", "dateUpdated": "2026-08-05T12:09:29.032Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:09:29.032Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: hci_sync: fix race in hci_cmd_sync_dequeue_once\n\nhci_cmd_sync_dequeue_once() does lookup and then cancel\nthe entry under two separate lock sections. Meanwhile,\nhci_cmd_sync_work() can also delete the same entry,\nleading to double list_del() and \"UAF\".\n\nFix this by holding cmd_sync_work_lock across both\nlookup and cancel, so that the entry cannot be removed\nconcurrently." } ], "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 flaw is in the Bluetooth HCI command-sync queue, and the create-connection entries it manages are queued and aborted in response to LE/ACL link events from a peer in radio range (advertising reports driving `check_pending_le_conn()`, and `le_conn_timeout` when the peer stops responding). An attacker within Bluetooth range can drive both the queue and cancel sides without any local access.\nAC:L - The attacker controls both sides of the race — repeatedly forcing connection attempts and aborts cycles `hci_cancel_connect_sync()` against the `cmd_sync_work` kthread draining the same list entry, and the attempt can be retried without limit. The window sits between two lock acquisitions in the same function with the worker on a separate CPU, making it readily hit on SMP.\nPR:N - The adjacent attacker holds no credentials on the target: the LE create-connection queue/cancel cycle happens entirely before pairing or authentication completes. Even on the purely local path only an unprivileged AF_BLUETOOTH socket is needed, since `l2cap_sock_create()` gates only SOCK_RAW behind CAP_NET_RAW.\nUI:N - Background LE auto-connect and connection-timeout handling proceed autonomously in kernel workqueues with no victim action. No file must be opened, device mounted, or prompt accepted.\nS:U - The corruption is confined to kernel heap objects managed by the same kernel security authority; there is no VM, IOMMU, or sandbox boundary crossed. Impact is standard in-kernel compromise.\nC:H - The use-after-free reads `entry->destroy` and `entry->data` out of a freed kmalloc-64 object and dereferences them, and the resulting hijacked call plus double-`list_del` write primitive can be leveraged into arbitrary kernel memory disclosure. Freed-slab reads alone already expose adjacent kernel heap contents.\nI:H - `_hci_cmd_sync_cancel_entry()` calls a function pointer read from freed memory and then performs a double `list_del()` that writes attacker-groomable pointers to attacker-groomable addresses, plus a double `kfree()`. That combination is a direct control-flow-hijack and arbitrary-write path to full kernel code execution.\nA:H - Without successful grooming the same code path dereferences LIST_POISON or freed slab contents, producing a `list_del corruption` BUG, GPF, or panic. The double free additionally corrupts the slab allocator, crashing the system." } ] } ], "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": "f00f36db76eb8fd10d13e80e2590f23b5beaa54d", "lessThan": "0a94f7e017438935c09ef833a1aa908ad9875213", "status": "affected", "versionType": "git" }, { "version": "1499f79995c7ee58e3bfeeff75f6d1b37dcda881", "lessThan": "932c0a4f77ac13e526fdd5b42914d29c9821d389", "status": "affected", "versionType": "git" }, { "version": "505ea2b295929e7be2b4e1bc86ee31cb7862fb01", "lessThan": "ae76cf6c2c842944c6514c57df54d728f1916553", "status": "affected", "versionType": "git" }, { "version": "505ea2b295929e7be2b4e1bc86ee31cb7862fb01", "lessThan": "9cd536970192b72257afcdfba0bfc09993e6f19c", "status": "affected", "versionType": "git" }, { "version": "505ea2b295929e7be2b4e1bc86ee31cb7862fb01", "lessThan": "09b0cd1297b4dbfe736aeaa0ceeab2265f47f772", "status": "affected", "versionType": "git" }, { "version": "357603f4d396d85fbf0045512efaf1d7f7394ed7", "status": "affected", "versionType": "git" }, { "version": "6.1.120", "lessThan": "6.1.159", "status": "affected", "versionType": "semver" }, { "version": "6.6.51", "lessThan": "6.6.117", "status": "affected", "versionType": "semver" }, { "version": "6.8.9", "lessThan": "6.9", "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": "6.9", "status": "affected" }, { "version": "0", "lessThan": "6.9", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.159", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.117", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.58", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.17.8", "lessThanOrEqual": "6.17.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18", "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": "6.1.120", "versionEndExcluding": "6.1.159" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6.51", "versionEndExcluding": "6.6.117" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.9", "versionEndExcluding": "6.12.58" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.9", "versionEndExcluding": "6.17.8" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.9", "versionEndExcluding": "6.18" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.8.9" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/0a94f7e017438935c09ef833a1aa908ad9875213" }, { "url": "https://git.kernel.org/stable/c/932c0a4f77ac13e526fdd5b42914d29c9821d389" }, { "url": "https://git.kernel.org/stable/c/ae76cf6c2c842944c6514c57df54d728f1916553" }, { "url": "https://git.kernel.org/stable/c/9cd536970192b72257afcdfba0bfc09993e6f19c" }, { "url": "https://git.kernel.org/stable/c/09b0cd1297b4dbfe736aeaa0ceeab2265f47f772" } ], "title": "Bluetooth: hci_sync: fix race in hci_cmd_sync_dequeue_once", "x_generator": { "engine": "bippy-1.2.0" } } } }