Bluetooth: hci_event: Fix UAF in hci_acl_create_conn_sync
Key facts
- Attack vector
- Adjacent network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 33 fixed, 2 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.
Summary
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_event: Fix UAF in hci_acl_create_conn_sync This fixes the following UFA in hci_acl_create_conn_sync where a connection still pending is command submission (conn->state == BT_OPEN) maybe freed, also since this also can happen with the likes of hci_le_create_conn_sync fix it as well: BUG: KASAN: slab-use-after-free in hci_acl_create_conn_sync+0x5ef/0x790 net/bluetooth/hci_sync.c:6861 Write of size 2 at addr ffff88805ffcc038 by task kworker/u11:2/9541 CPU: 1 UID: 0 PID: 9541 Comm: kworker/u11:2 Not tainted 6.16.0-rc7 #3 PREEMPT(full) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 Workqueue: hci3 hci_cmd_sync_work Call Trace: <TASK> dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x230 mm/kasan/report.c:480 kasan_report+0x118/0x150 mm/kasan/report.c:593 hci_acl_create_conn_sync+0x5ef/0x790 net/bluetooth/hci_sync.c:6861 hci_cmd_sync_work+0x210/0x3a0 net/bluetooth/hci_sync.c:332 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 home/kwqcheii/source/fuzzing/kernel/kasan/linux-6.16-rc7/arch/x86/entry/entry_64.S:245 </TASK> Allocated by task 123736: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4359 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] __hci_conn_add+0x233/0x1b30 net/bluetooth/hci_conn.c:939 hci_conn_add_unset net/bluetooth/hci_conn.c:1051 [inline] hci_connect_acl+0x16c/0x4e0 net/bluetooth/hci_conn.c:1634 pair_device+0x418/0xa70 net/bluetooth/mgmt.c:3556 hci_mgmt_cmd+0x9c9/0xef0 net/bluetooth/hci_sock.c:1719 hci_sock_sendmsg+0x6ca/0xef0 net/bluetooth/hci_sock.c:1839 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:727 sock_write_iter+0x258/0x330 net/socket.c:1131 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x54b/0xa90 fs/read_write.c:686 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 103680: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2381 [inline] slab_free mm/slub.c:4643 [inline] kfree+0x18e/0x440 mm/slub.c:4842 device_release+0x9c/0x1c0 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x22b/0x480 lib/kobject.c:737 hci_conn_cleanup net/bluetooth/hci_conn.c:175 [inline] hci_conn_del+0x8ff/0xcb0 net/bluetooth/hci_conn.c:1173 hci_conn_complete_evt+0x3c7/0x1040 net/bluetooth/hci_event.c:3199 hci_event_func net/bluetooth/hci_event.c:7477 [inline] hci_event_packet+0x7e0/0x1200 net/bluetooth/hci_event.c:7531 hci_rx_work+0x46a/0xe80 net/bluetooth/hci_core.c:4070 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 home/kwqcheii/sour ---truncated---
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA Linux (Linux) Fixed in 6.1.155, 6.6.109, 6.12.50, 6.16.10, 6.17
Red Hat 9 advisories
- RHSA-2026:44385 Released 2026-07-23 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat CodeReady Linux Builder EUS (v.9.6) kernel-tools-libs-devel-5.14.0-570.129.1.el9_6, libperf-5.14.0-570.129.1.el9_6
- Red Hat Enterprise Linux AppStream EUS (v.9.6) kernel-64k-debug-devel-5.14.0-570.129.1.el9_6, kernel-64k-debug-devel-matched-5.14.0-570.129.1.el9_6, kernel-64k-devel-5.14.0-570.129.1.el9_6 +12
- Red Hat Enterprise Linux BaseOS EUS (v.9.6) kernel-5.14.0-570.129.1.el9_6, kernel-64k-5.14.0-570.129.1.el9_6, kernel-64k-core-5.14.0-570.129.1.el9_6 +28
- Red Hat Enterprise Linux Real Time EUS (v.9.6) kernel-rt-5.14.0-570.129.1.el9_6, kernel-rt-64k-5.14.0-570.129.1.el9_6, kernel-rt-64k-core-5.14.0-570.129.1.el9_6 +21
- Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6) kernel-rt-5.14.0-570.129.1.el9_6, kernel-rt-core-5.14.0-570.129.1.el9_6, kernel-rt-debug-5.14.0-570.129.1.el9_6 +11
- RHSA-2026:0576 Released 2026-01-14 · Red Hat rating Importantkernel security update
- Red Hat Enterprise Linux AppStream E4S (v.9.0) kernel-debug-devel-5.14.0-70.161.1.el9_0, kernel-debug-devel-matched-5.14.0-70.161.1.el9_0, kernel-devel-5.14.0-70.161.1.el9_0 +5
- Red Hat Enterprise Linux BaseOS E4S (v.9.0) bpftool-5.14.0-70.161.1.el9_0, kernel-5.14.0-70.161.1.el9_0, kernel-abi-stablelists-5.14.0-70.161.1.el9_0 +14
- RHSA-2026:0535 Released 2026-01-14 · Red Hat rating Importantkernel security update
- Red Hat Enterprise Linux AppStream E4S (v.9.2) kernel-64k-debug-devel-5.14.0-284.152.1.el9_2, kernel-64k-debug-devel-matched-5.14.0-284.152.1.el9_2, kernel-64k-devel-5.14.0-284.152.1.el9_2 +10
- Red Hat Enterprise Linux BaseOS E4S (v.9.2) bpftool-7.0.0-284.152.1.el9_2, kernel-5.14.0-284.152.1.el9_2, kernel-64k-5.14.0-284.152.1.el9_2 +29
Show 6 more Red Hat advisories
- RHSA-2026:0534 Released 2026-01-14 · Red Hat rating Importantkernel-rt security update
- Red Hat Enterprise Linux Real Time E4S (v.9.2) kernel-rt-5.14.0-284.152.1.rt14.437.el9_2, kernel-rt-core-5.14.0-284.152.1.rt14.437.el9_2, kernel-rt-debug-5.14.0-284.152.1.rt14.437.el9_2 +9
- Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2) kernel-rt-5.14.0-284.152.1.rt14.437.el9_2, kernel-rt-core-5.14.0-284.152.1.rt14.437.el9_2, kernel-rt-debug-5.14.0-284.152.1.rt14.437.el9_2 +11
- RHSA-2026:0537 Released 2026-01-14 · Red Hat rating Importantkernel-rt security update
- Red Hat Enterprise Linux NFV E4S (v.9.0) kernel-rt-5.14.0-70.161.1.rt21.233.el9_0, kernel-rt-core-5.14.0-70.161.1.rt21.233.el9_0, kernel-rt-debug-5.14.0-70.161.1.rt21.233.el9_0 +9
- Red Hat Enterprise Linux Real Time E4S (v.9.0) kernel-rt-5.14.0-70.161.1.rt21.233.el9_0, kernel-rt-core-5.14.0-70.161.1.rt21.233.el9_0, kernel-rt-debug-5.14.0-70.161.1.rt21.233.el9_0 +7
- RHSA-2026:0489 Released 2026-01-13 · Red Hat rating Importantkernel security update
- Red Hat CodeReady Linux Builder EUS (v.9.4) kernel-tools-libs-devel-5.14.0-427.106.1.el9_4, libperf-5.14.0-427.106.1.el9_4
- Red Hat Enterprise Linux AppStream EUS (v.9.4) kernel-64k-debug-devel-5.14.0-427.106.1.el9_4, kernel-64k-debug-devel-matched-5.14.0-427.106.1.el9_4, kernel-64k-devel-5.14.0-427.106.1.el9_4 +11
- Red Hat Enterprise Linux BaseOS EUS (v.9.4) bpftool-7.3.0-427.106.1.el9_4, kernel-5.14.0-427.106.1.el9_4, kernel-64k-5.14.0-427.106.1.el9_4 +29
- Red Hat Enterprise Linux Real Time EUS (v.9.4) kernel-rt-5.14.0-427.106.1.el9_4, kernel-rt-core-5.14.0-427.106.1.el9_4, kernel-rt-debug-5.14.0-427.106.1.el9_4 +9
- Red Hat Enterprise Linux Real Time for NFV EUS (v.9.4) kernel-rt-5.14.0-427.106.1.el9_4, kernel-rt-core-5.14.0-427.106.1.el9_4, kernel-rt-debug-5.14.0-427.106.1.el9_4 +11
- RHSA-2026:0271 Released 2026-01-08 · Red Hat rating Moderatekernel security update
- Red Hat Enterprise Linux AppStream EUS (v. 10.0) kernel-64k-debug-devel-6.12.0-55.52.1.el10_0, kernel-64k-debug-devel-matched-6.12.0-55.52.1.el10_0, kernel-64k-devel-6.12.0-55.52.1.el10_0 +8
- Red Hat Enterprise Linux BaseOS EUS (v. 10.0) kernel-6.12.0-55.52.1.el10_0, kernel-64k-6.12.0-55.52.1.el10_0, kernel-64k-core-6.12.0-55.52.1.el10_0 +28
- Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) kernel-tools-libs-devel-6.12.0-55.52.1.el10_0
- Red Hat Enterprise Linux Real Time EUS (v. 10.0) kernel-rt-6.12.0-55.52.1.el10_0, kernel-rt-64k-6.12.0-55.52.1.el10_0, kernel-rt-64k-core-6.12.0-55.52.1.el10_0 +21
- Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0) kernel-rt-6.12.0-55.52.1.el10_0, kernel-rt-core-6.12.0-55.52.1.el10_0, kernel-rt-debug-6.12.0-55.52.1.el10_0 +11
- RHSA-2025:22854 Released 2025-12-09 · Red Hat rating Moderatekernel security update
- Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-124.20.1.el10_1, kernel-64k-debug-devel-matched-6.12.0-124.20.1.el10_1, kernel-64k-devel-6.12.0-124.20.1.el10_1 +12
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- Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-124.20.1.el10_1, libperf-6.12.0-124.20.1.el10_1
- Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-124.20.1.el10_1, kernel-rt-64k-6.12.0-124.20.1.el10_1, kernel-rt-64k-core-6.12.0-124.20.1.el10_1 +21
- Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-124.20.1.el10_1, kernel-rt-core-6.12.0-124.20.1.el10_1, kernel-rt-debug-6.12.0-124.20.1.el10_1 +9
- RHSA-2025:21469 Released 2025-11-17 · Red Hat rating Moderatekernel security update
- Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-611.8.1.el9_7, kernel-64k-debug-devel-matched-5.14.0-611.8.1.el9_7, kernel-64k-devel-5.14.0-611.8.1.el9_7 +12
- Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-611.8.1.el9_7, kernel-64k-5.14.0-611.8.1.el9_7, kernel-64k-core-5.14.0-611.8.1.el9_7 +28
- Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-611.8.1.el9_7, libperf-5.14.0-611.8.1.el9_7
- Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-611.8.1.el9_7, kernel-rt-64k-5.14.0-611.8.1.el9_7, kernel-rt-64k-core-5.14.0-611.8.1.el9_7 +21
- Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-611.8.1.el9_7, kernel-rt-core-5.14.0-611.8.1.el9_7, kernel-rt-debug-5.14.0-611.8.1.el9_7 +9
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 9 | Affected | No fix yet |
| Red Hat CodeReady Linux Builder EUS (v.9.4) | Fixed | RHSA-2026:0489 |
| Red Hat CodeReady Linux Builder EUS (v.9.6) | Fixed | RHSA-2026:44385 |
| Red Hat Enterprise Linux AppStream (v. 10) | Fixed | RHSA-2025:22854 |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2025:21469 |
| Red Hat Enterprise Linux AppStream E4S (v.9.0) | Fixed | RHSA-2026:0576 |
| Red Hat Enterprise Linux AppStream E4S (v.9.2) | Fixed | RHSA-2026:0535 |
| Red Hat Enterprise Linux AppStream EUS (v. 10.0) | Fixed | RHSA-2026:0271 |
| Red Hat Enterprise Linux AppStream EUS (v.9.4) | Fixed | RHSA-2026:0489 |
| Red Hat Enterprise Linux AppStream EUS (v.9.6) | Fixed | RHSA-2026:44385 |
| Red Hat Enterprise Linux BaseOS (v. 10) | Fixed | RHSA-2025:22854 |
| Red Hat Enterprise Linux BaseOS (v. 9) | Fixed | RHSA-2025:21469 |
| Red Hat Enterprise Linux BaseOS E4S (v.9.0) | Fixed | RHSA-2026:0576 |
| Red Hat Enterprise Linux BaseOS E4S (v.9.2) | Fixed | RHSA-2026:0535 |
| Red Hat Enterprise Linux BaseOS EUS (v. 10.0) | Fixed | RHSA-2026:0271 |
| Red Hat Enterprise Linux BaseOS EUS (v.9.4) | Fixed | RHSA-2026:0489 |
| Red Hat Enterprise Linux BaseOS EUS (v.9.6) | Fixed | RHSA-2026:44385 |
| Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) | Fixed | RHSA-2025:22854 |
| Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) | Fixed | RHSA-2025:21469 |
| Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) | Fixed | RHSA-2026:0271 |
| Red Hat Enterprise Linux NFV E4S (v.9.0) | Fixed | RHSA-2026:0537 |
| Red Hat Enterprise Linux Real Time (v. 10) | Fixed | RHSA-2025:22854 |
| Red Hat Enterprise Linux Real Time (v. 9) | Fixed | RHSA-2025:21469 |
| Red Hat Enterprise Linux Real Time E4S (v.9.0) | Fixed | RHSA-2026:0537 |
| Red Hat Enterprise Linux Real Time E4S (v.9.2) | Fixed | RHSA-2026:0534 |
| Red Hat Enterprise Linux Real Time EUS (v. 10.0) | Fixed | RHSA-2026:0271 |
| Red Hat Enterprise Linux Real Time EUS (v.9.4) | Fixed | RHSA-2026:0489 |
| Red Hat Enterprise Linux Real Time EUS (v.9.6) | Fixed | RHSA-2026:44385 |
| Red Hat Enterprise Linux Real Time for NFV (v. 10) | Fixed | RHSA-2025:22854 |
| Red Hat Enterprise Linux Real Time for NFV (v. 9) | Fixed | RHSA-2025:21469 |
| Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2) | Fixed | RHSA-2026:0534 |
| Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0) | Fixed | RHSA-2026:0271 |
| Red Hat Enterprise Linux Real Time for NFV EUS (v.9.4) | Fixed | RHSA-2026:0489 |
| Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6) | Fixed | RHSA-2026:44385 |
Not affected: 7 products
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux AppStream EUS (v. 10.0)
- Red Hat Enterprise Linux BaseOS EUS (v. 10.0)
- Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0)
- Red Hat Enterprise Linux Real Time EUS (v. 10.0)
- Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0)
Timeline
- 2026-10-02 Threatist record created from CVE-2025-39982
- 2026-10-03 Alias added: GHSA-jm87-4mhh-83rp
- 2026-10-16 CISA SSVC decision points changed
- 2026-10-16 Priority changed: LOW → MEDIUM
References
Other 5
- https://git.kernel.org/stable/c/6243bda271a628c48875e3e473206e7f584892ce
- https://git.kernel.org/stable/c/bcce99f613163a43de24674b717e7a6c135fc879
- https://git.kernel.org/stable/c/484c7d571a3d1b3fd298fa691b660438c4548a53
- https://git.kernel.org/stable/c/a78fd4fc5694ecb3b97deb2ad9eaebd67b4d2b08
- https://git.kernel.org/stable/c/9e622804d57e2d08f0271200606bd1270f75126f
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Sources
- CVE-2025-39982 · CVE Program
- CVE-2025-39982 · NVD
- FIRST EPSS
- GHSA-jm87-4mhh-83rp · GitHub Advisory Database · CC BY 4.0
- CVE-2025-39982 · Red Hat security data · CC BY 4.0
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