{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2022-49910", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-05-01T14:05:17.247Z", "datePublished": "2025-05-01T14:10:53.010Z", "dateUpdated": "2026-08-05T08:56:39.541Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T08:56:39.541Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: Fix use-after-free caused by l2cap_reassemble_sdu\n\nFix the race condition between the following two flows that run in\nparallel:\n\n1. l2cap_reassemble_sdu -> chan->ops->recv (l2cap_sock_recv_cb) ->\n __sock_queue_rcv_skb.\n\n2. bt_sock_recvmsg -> skb_recv_datagram, skb_free_datagram.\n\nAn SKB can be queued by the first flow and immediately dequeued and\nfreed by the second flow, therefore the callers of l2cap_reassemble_sdu\ncan't use the SKB after that function returns. However, some places\ncontinue accessing struct l2cap_ctrl that resides in the SKB's CB for a\nshort time after l2cap_reassemble_sdu returns, leading to a\nuse-after-free condition (the stack trace is below, line numbers for\nkernel 5.19.8).\n\nFix it by keeping a local copy of struct l2cap_ctrl.\n\nBUG: KASAN: use-after-free in l2cap_rx_state_recv (net/bluetooth/l2cap_core.c:6906) bluetooth\nRead of size 1 at addr ffff88812025f2f0 by task kworker/u17:3/43169\n\nWorkqueue: hci0 hci_rx_work [bluetooth]\nCall Trace:\n \n dump_stack_lvl (lib/dump_stack.c:107 (discriminator 4))\n print_report.cold (mm/kasan/report.c:314 mm/kasan/report.c:429)\n ? l2cap_rx_state_recv (net/bluetooth/l2cap_core.c:6906) bluetooth\n kasan_report (mm/kasan/report.c:162 mm/kasan/report.c:493)\n ? l2cap_rx_state_recv (net/bluetooth/l2cap_core.c:6906) bluetooth\n l2cap_rx_state_recv (net/bluetooth/l2cap_core.c:6906) bluetooth\n l2cap_rx (net/bluetooth/l2cap_core.c:7236 net/bluetooth/l2cap_core.c:7271) bluetooth\n ret_from_fork (arch/x86/entry/entry_64.S:306)\n \n\nAllocated by task 43169:\n kasan_save_stack (mm/kasan/common.c:39)\n __kasan_slab_alloc (mm/kasan/common.c:45 mm/kasan/common.c:436 mm/kasan/common.c:469)\n kmem_cache_alloc_node (mm/slab.h:750 mm/slub.c:3243 mm/slub.c:3293)\n __alloc_skb (net/core/skbuff.c:414)\n l2cap_recv_frag (./include/net/bluetooth/bluetooth.h:425 net/bluetooth/l2cap_core.c:8329) bluetooth\n l2cap_recv_acldata (net/bluetooth/l2cap_core.c:8442) bluetooth\n hci_rx_work (net/bluetooth/hci_core.c:3642 net/bluetooth/hci_core.c:3832) bluetooth\n process_one_work (kernel/workqueue.c:2289)\n worker_thread (./include/linux/list.h:292 kernel/workqueue.c:2437)\n kthread (kernel/kthread.c:376)\n ret_from_fork (arch/x86/entry/entry_64.S:306)\n\nFreed by task 27920:\n kasan_save_stack (mm/kasan/common.c:39)\n kasan_set_track (mm/kasan/common.c:45)\n kasan_set_free_info (mm/kasan/generic.c:372)\n ____kasan_slab_free (mm/kasan/common.c:368 mm/kasan/common.c:328)\n slab_free_freelist_hook (mm/slub.c:1780)\n kmem_cache_free (mm/slub.c:3536 mm/slub.c:3553)\n skb_free_datagram (./include/net/sock.h:1578 ./include/net/sock.h:1639 net/core/datagram.c:323)\n bt_sock_recvmsg (net/bluetooth/af_bluetooth.c:295) bluetooth\n l2cap_sock_recvmsg (net/bluetooth/l2cap_sock.c:1212) bluetooth\n sock_read_iter (net/socket.c:1087)\n new_sync_read (./include/linux/fs.h:2052 fs/read_write.c:401)\n vfs_read (fs/read_write.c:482)\n ksys_read (fs/read_write.c:620)\n do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)\n entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)" } ], "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 bug is reached by processing Bluetooth ACL/L2CAP I-frames in hci_rx_work → l2cap_recv_acldata → l2cap_data_rcv → l2cap_rx_state_recv/l2cap_stream_rx, which requires an attacker on the same Bluetooth segment.\nAC:L - An adjacent peer can reliably drive the receive path by sending ERTM/streaming I-frames on an established channel; on SMP, a normal blocking socket reader frees the skb in the race window the attacker creates, and a local app plus attacker-controlled peer can control both sides.\nPR:N - Exploitation is via unauthenticated Bluetooth L2CAP data handling in the kernel RX path; the adjacent attacker needs no privileges on the victim host (consistent with other Bluetooth L2CAP UAF scores).\nUI:N - No additional user action is required beyond an active L2CAP ERTM/streaming channel (for example RFCOMM or an already-paired/auto-connecting peer whose socket is being read by userspace).\nS:U - This is in-kernel heap UAF within the Bluetooth stack and does not cross a separate security authority such as a VM or IOMMU boundary.\nC:H - Use-after-free of the skb (including cb-resident l2cap_ctrl) enables heap reuse and arbitrary kernel memory disclosure primitives.\nI:H - Post-free use of control feeds l2cap_retransmit_all and channel sequence updates, so the UAF can be turned into heap corruption and control-flow hijacking.\nA:H - The UAF is a demonstrated KASAN use-after-free on the HCI RX workqueue and can cause kernel oops/panic even without full exploitation." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/bluetooth/l2cap_core.c" ], "versions": [ { "version": "4b51dae96731c9d82f5634e75ac7ffd3b9c1b060", "lessThan": "dc30e05bb18852303084430c03ca76e69257d9ea", "status": "affected", "versionType": "git" }, { "version": "4b51dae96731c9d82f5634e75ac7ffd3b9c1b060", "lessThan": "03af22e23b96fb7ef75fb7885407ef457e8b403d", "status": "affected", "versionType": "git" }, { "version": "4b51dae96731c9d82f5634e75ac7ffd3b9c1b060", "lessThan": "6c7407bfbeafc80a04e6eaedcf34d378532a04f2", "status": "affected", "versionType": "git" }, { "version": "4b51dae96731c9d82f5634e75ac7ffd3b9c1b060", "lessThan": "4cd094fd5d872862ca278e15b9b51b07e915ef3f", "status": "affected", "versionType": "git" }, { "version": "4b51dae96731c9d82f5634e75ac7ffd3b9c1b060", "lessThan": "cb1c012099ef5904cd468bdb8d6fcdfdd9bcb569", "status": "affected", "versionType": "git" }, { "version": "4b51dae96731c9d82f5634e75ac7ffd3b9c1b060", "lessThan": "8278a87bb1eeea94350d675ef961ee5a03341fde", "status": "affected", "versionType": "git" }, { "version": "4b51dae96731c9d82f5634e75ac7ffd3b9c1b060", "lessThan": "9a04161244603f502c6e453913e51edd59cb70c1", "status": "affected", "versionType": "git" }, { "version": "4b51dae96731c9d82f5634e75ac7ffd3b9c1b060", "lessThan": "3aff8aaca4e36dc8b17eaa011684881a80238966", "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/l2cap_core.c" ], "versions": [ { "version": "3.6", "status": "affected" }, { "version": "0", "lessThan": "3.6", "status": "unaffected", "versionType": "semver" }, { "version": "4.9.333", "lessThanOrEqual": "4.9.*", "status": "unaffected", "versionType": "semver" }, { "version": "4.14.299", "lessThanOrEqual": "4.14.*", "status": "unaffected", "versionType": "semver" }, { "version": "4.19.265", "lessThanOrEqual": "4.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.4.224", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.154", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.78", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.0.8", "lessThanOrEqual": "6.0.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1", "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": "3.6", "versionEndExcluding": "4.9.333" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.6", "versionEndExcluding": "4.14.299" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.6", "versionEndExcluding": "4.19.265" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.6", "versionEndExcluding": "5.4.224" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.6", "versionEndExcluding": "5.10.154" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.6", "versionEndExcluding": "5.15.78" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.6", "versionEndExcluding": "6.0.8" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.6", "versionEndExcluding": "6.1" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/dc30e05bb18852303084430c03ca76e69257d9ea" }, { "url": "https://git.kernel.org/stable/c/03af22e23b96fb7ef75fb7885407ef457e8b403d" }, { "url": "https://git.kernel.org/stable/c/6c7407bfbeafc80a04e6eaedcf34d378532a04f2" }, { "url": "https://git.kernel.org/stable/c/4cd094fd5d872862ca278e15b9b51b07e915ef3f" }, { "url": "https://git.kernel.org/stable/c/cb1c012099ef5904cd468bdb8d6fcdfdd9bcb569" }, { "url": "https://git.kernel.org/stable/c/8278a87bb1eeea94350d675ef961ee5a03341fde" }, { "url": "https://git.kernel.org/stable/c/9a04161244603f502c6e453913e51edd59cb70c1" }, { "url": "https://git.kernel.org/stable/c/3aff8aaca4e36dc8b17eaa011684881a80238966" } ], "title": "Bluetooth: L2CAP: Fix use-after-free caused by l2cap_reassemble_sdu", "x_generator": { "engine": "bippy-1.2.0" } } } }