CVE-2025-21969
- Source
- https://cve.org/CVERecord?id=CVE-2025-21969
- Import Source
- https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2025-21969.json
- JSON Data
- https://api.test.osv.dev/v1/vulns/CVE-2025-21969
- Downstream
- Related
- Published
- 2025-04-01T15:47:03Z
- Modified
- 2026-05-18T05:56:15Z
- Severity
-
- 7.8 (High) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
- Summary
- Bluetooth: L2CAP: Fix slab-use-after-free Read in l2cap_send_cmd
- Details
-
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: Fix slab-use-after-free Read in l2cap_send_cmd
After the hci sync command releases l2cap_conn, the hci receive data work queue references the released l2cap_conn when sending to the upper layer. Add hci dev lock to the hci receive data work queue to synchronize the two.
[1] BUG: KASAN: slab-use-after-free in l2cap_send_cmd+0x187/0x8d0 net/bluetooth/l2cap_core.c:954 Read of size 8 at addr ffff8880271a4000 by task kworker/u9:2/5837
CPU: 0 UID: 0 PID: 5837 Comm: kworker/u9:2 Not tainted 6.13.0-rc5-syzkaller-00163-gab75170520d4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: hci1 hci_rx_work Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 l2cap_build_cmd net/bluetooth/l2cap_core.c:2964 [inline] l2cap_send_cmd+0x187/0x8d0 net/bluetooth/l2cap_core.c:954 l2cap_sig_send_rej net/bluetooth/l2cap_core.c:5502 [inline] l2cap_sig_channel net/bluetooth/l2cap_core.c:5538 [inline] l2cap_recv_frame+0x221f/0x10db0 net/bluetooth/l2cap_core.c:6817 hci_acldata_packet net/bluetooth/hci_core.c:3797 [inline] hci_rx_work+0x508/0xdb0 net/bluetooth/hci_core.c:4040 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Allocated by task 5837: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4329 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] l2cap_conn_add+0xa9/0x8e0 net/bluetooth/l2cap_core.c:6860 l2cap_connect_cfm+0x115/0x1090 net/bluetooth/l2cap_core.c:7239 hci_connect_cfm include/net/bluetooth/hci_core.h:2057 [inline] hci_remote_features_evt+0x68e/0xac0 net/bluetooth/hci_event.c:3726 hci_event_func net/bluetooth/hci_event.c:7473 [inline] hci_event_packet+0xac2/0x1540 net/bluetooth/hci_event.c:7525 hci_rx_work+0x3f3/0xdb0 net/bluetooth/hci_core.c:4035 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 54: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2353 [inline] slab_free mm/slub.c:4613 [inline] kfree+0x196/0x430 mm/slub.c:4761 l2cap_connect_cfm+0xcc/0x1090 net/bluetooth/l2cap_core.c:7235 hci_connect_cfm include/net/bluetooth/hci_core.h:2057 [inline] hci_conn_failed+0x287/0x400 net/bluetooth/hci_conn.c:1266 hci_abort_conn_sync+0x56c/0x11f0 net/bluetooth/hci_sync.c:5603 hci_cmd_sync_work+0x22b/0x400 net/bluetooth/hci_sync.c:332 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entr ---truncated---
- Database specific
{ "cna_assigner": "Linux", "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/21xxx/CVE-2025-21969.json" }- References
-
- https://git.kernel.org/stable/c/7790a79c6fce8d5d552bc64f5c82819f719e4f28
- https://git.kernel.org/stable/c/b4f82f9ed43aefa79bec2504ae8c29be0c0f5d1d
- https://git.kernel.org/stable/c/c96cce853542b3b13da3738f35ef1be8cfcc9d1d
- https://git.kernel.org/stable/c/f8094625a591eeb0b75b1bd9e713fac1d93f5ca9
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/21xxx/CVE-2025-21969.json
- https://nvd.nist.gov/vuln/detail/CVE-2025-21969
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Affected packages
Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Affected ranges
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced9b3628d79b46f06157affc56fdb218fdd4988321Fixedc96cce853542b3b13da3738f35ef1be8cfcc9d1dFixedf8094625a591eeb0b75b1bd9e713fac1d93f5ca9Fixed7790a79c6fce8d5d552bc64f5c82819f719e4f28Fixedb4f82f9ed43aefa79bec2504ae8c29be0c0f5d1d
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced0 Unknown introduced commit / All previous commits are affectedLast Affected995c917d6818b39308ac6baf3f6573cb0486a238