CVE-2025-40309

EPSS 0.0%
  • Published: 2025-12-08T01:16:03.207

In the Linux kernel, the following vulnerability has been resolved:

Bluetooth: SCO: Fix UAF on sco_conn_free

BUG: KASAN: slab-use-after-free in sco_conn_free net/bluetooth/sco.c:87 [inline]
BUG: KASAN: slab-use-after-free in kref_put include/linux/kref.h:65 [inline]
BUG: KASAN: slab-use-after-free in sco_conn_put+0xdd/0x410
net/bluetooth/sco.c:107
Write of size 8 at addr ffff88811cb96b50 by task kworker/u17:4/352

CPU: 1 UID: 0 PID: 352 Comm: kworker/u17:4 Not tainted
6.17.0-rc5-g717368f83676 #4 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
Workqueue: hci13 hci_cmd_sync_work
Call Trace:

__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x10b/0x170 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0x191/0x550 mm/kasan/report.c:482
kasan_report+0xc4/0x100 mm/kasan/report.c:595
sco_conn_free net/bluetooth/sco.c:87 [inline]
kref_put include/linux/kref.h:65 [inline]
sco_conn_put+0xdd/0x410 net/bluetooth/sco.c:107
sco_connect_cfm+0xb4/0xae0 net/bluetooth/sco.c:1441
hci_connect_cfm include/net/bluetooth/hci_core.h:2082 [inline]
hci_conn_failed+0x20a/0x2e0 net/bluetooth/hci_conn.c:1313
hci_conn_unlink+0x55f/0x810 net/bluetooth/hci_conn.c:1121
hci_conn_del+0xb6/0x1110 net/bluetooth/hci_conn.c:1147
hci_abort_conn_sync+0x8c5/0xbb0 net/bluetooth/hci_sync.c:5689
hci_cmd_sync_work+0x281/0x380 net/bluetooth/hci_sync.c:332
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0x77e/0x1040 kernel/workqueue.c:3319
worker_thread+0xbee/0x1200 kernel/workqueue.c:3400
kthread+0x3c7/0x870 kernel/kthread.c:463
ret_from_fork+0x13a/0x1e0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Allocated by task 31370:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x30/0x70 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:388 [inline]
__kasan_kmalloc+0x82/0x90 mm/kasan/common.c:405
kasan_kmalloc include/linux/kasan.h:260 [inline]
__do_kmalloc_node mm/slub.c:4382 [inline]
__kmalloc_noprof+0x22f/0x390 mm/slub.c:4394
kmalloc_noprof include/linux/slab.h:909 [inline]
sk_prot_alloc+0xae/0x220 net/core/sock.c:2239
sk_alloc+0x34/0x5a0 net/core/sock.c:2295
bt_sock_alloc+0x3c/0x330 net/bluetooth/af_bluetooth.c:151
sco_sock_alloc net/bluetooth/sco.c:562 [inline]
sco_sock_create+0xc0/0x350 net/bluetooth/sco.c:593
bt_sock_create+0x161/0x3b0 net/bluetooth/af_bluetooth.c:135
__sock_create+0x3ad/0x780 net/socket.c:1589
sock_create net/socket.c:1647 [inline]
__sys_socket_create net/socket.c:1684 [inline]
__sys_socket+0xd5/0x330 net/socket.c:1731
__do_sys_socket net/socket.c:1745 [inline]
__se_sys_socket net/socket.c:1743 [inline]
__x64_sys_socket+0x7a/0x90 net/socket.c:1743
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xc7/0x240 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 31374:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x30/0x70 mm/kasan/common.c:68
kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:243 [inline]
__kasan_slab_free+0x3d/0x50 mm/kasan/common.c:275
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2428 [inline]
slab_free mm/slub.c:4701 [inline]
kfree+0x199/0x3b0 mm/slub.c:4900
sk_prot_free net/core/sock.c:2278 [inline]
__sk_destruct+0x4aa/0x630 net/core/sock.c:2373
sco_sock_release+0x2ad/0x300 net/bluetooth/sco.c:1333
__sock_release net/socket.c:649 [inline]
sock_close+0xb8/0x230 net/socket.c:1439
__fput+0x3d1/0x9e0 fs/file_table.c:468
task_work_run+0x206/0x2a0 kernel/task_work.c:227
get_signal+0x1201/0x1410 kernel/signal.c:2807
arch_do_signal_or_restart+0x34/0x740 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x68/0xc0 kernel/entry/common.c:40
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
s
—truncated—

Related CVE by CWE

No related CWE found.

Top CVE for Vendor

No vendor taxonomy on this entry.

Recently Exploited Similar Vulnerabilities

No recent KEV-listed items for this vendor/product.

How to fix CVE-2025-40309

CVE-2025-40309 is a unknown severity vulnerability affecting the affected product.

Description: In the Linux kernel, the following vulnerability has been resolved: Bluetooth: SCO: Fix UAF on sco_conn_free BUG: KASAN: slab-use-after-free in sco_conn_free net/bluetooth/sco.c:87 [inline] BUG: KASAN: slab-use-after-free in kref_put include/linux/kref.h:65 [inline] BUG: KASAN: slab-use-after-free in sco_conn_put+0xdd/0x410 net/bluetooth/sco.c:107 Write of size 8 at addr ffff88811cb96b50 by task kworker/u17:4/352 CPU: 1 UID: 0 PID: 352 Comm: kworker/u17:4 Not […]

Exploit Difficulty: HARD
⏱️ Time to exploit: > 4 hours
🛠️ Required skills: Advanced security expertise
💰 Public exploits: Rare or not public

How to Fix:

1 Identify affected systems

- Check if you're running the affected product

2 Immediate actions

- Update to the latest patched version
- If patching is not immediately possible: restrict network exposure, apply least-privilege access

3 Verification

- Test the fix in a staging environment first
- Review logs for signs of exploitation
- Monitor for IOCs (Indicators of Compromise)

4 Long-term prevention

- Enable automatic security updates
- Set up vulnerability monitoring
- Review and harden security configurations

Exploit Difficulty Assessment

HARD
⏱️ Time to Exploit: > 4 hours
🛠️ Skills Required: Advanced security expertise
💰 Public Exploits: Rare or not public

Vulnerability Timeline

Dec 08, 2025
Vulnerability Published

CVE details first published to NVD database

Dec 08, 2025
Imported to Database

Added to this CVE tracking system

Detection Rules & IOCs

No specific detection rules generated for this vulnerability type.

No vendor/product data available.