cbcvebase.
CVE-2025-21969
published 2025-04-01

CVE-2025-21969: 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…

PriorityP339high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.24%
15.5th percentile
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

Affected

21 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.12.20-1 (forky)linux 6.12.20-1 (forky)
linuxlinux
linuxlinux
linuxlinux>= 5.17.14 < 5.185.18
linuxlinux>= 9b3628d79b46f06157affc56fdb218fdd4988321 < c96cce853542b3b13da3738f35ef1be8cfcc9d1dc96cce853542b3b13da3738f35ef1be8cfcc9d1d
linuxlinux>= 9b3628d79b46f06157affc56fdb218fdd4988321 < f8094625a591eeb0b75b1bd9e713fac1d93f5ca9f8094625a591eeb0b75b1bd9e713fac1d93f5ca9
linuxlinux>= 9b3628d79b46f06157affc56fdb218fdd4988321 < 7790a79c6fce8d5d552bc64f5c82819f719e4f287790a79c6fce8d5d552bc64f5c82819f719e4f28
linuxlinux>= 9b3628d79b46f06157affc56fdb218fdd4988321 < b4f82f9ed43aefa79bec2504ae8c29be0c0f5d1db4f82f9ed43aefa79bec2504ae8c29be0c0f5d1d
linuxlinux_kernel< 6.6.846.6.84
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.12.20-16.12.20-1
linuxlinux_kernel>= 0 < 6.12.20-16.12.20-1
linuxlinux_kernel>= 0 < 6.8.0-84.846.8.0-84.84
linuxlinux_kernel>= 6.13 < 6.13.86.13.8
linuxlinux_kernel>= 6.7 < 6.12.206.12.20
msrcazl3_kernel_6.6.82.1-1_on_azure_linux_3.0
msrcazl3_kernel_6.6.85.1-2_on_azure_linux_3.0
msrccbl2_kernel_5.15.186.1-1_on_cbl_mariner_2.0
msrccbl2_kernel_5.15.200.1-1_on_cbl_mariner_2.0
msrccbl2_kernel_5.15.202.1-1_on_cbl_mariner_2.0

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
vendor_msrc6.6MEDIUM
vendor_ubuntu5.9MEDIUM
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