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

Bluetooth: btusb: avoid NULL pointer dereference in skb_dequeue()

A NULL pointer dereference can occur in skb_dequeue() when processing a
QCA firmware crash dump on WCN7851 (0489:e0f3).

[ 93.672166] Bluetooth: hci0: ACL memdump size(589824)

[ 93.672475] BUG: kernel NULL pointer dereference, address: 0000000000000008
[ 93.672517] Workqueue: hci0 hci_devcd_rx [bluetooth]
[ 93.672598] RIP: 0010:skb_dequeue+0x50/0x80

The issue stems from handle_dump_pkt_qca() returning 0 even when a dump
packet is successfully processed. This is because it incorrectly
forwards the return value of hci_devcd_init() (which returns 0 on
success). As a result, the caller (btusb_recv_acl_qca() or
btusb_recv_evt_qca()) assumes the packet was not handled and passes it
to hci_recv_frame(), leading to premature kfree() of the skb.

Later, hci_devcd_rx() attempts to dequeue the same skb from the dump
queue, resulting in a NULL pointer dereference.

Fix this by:
1. Making handle_dump_pkt_qca() return 0 on success and negative errno
on failure, consistent with kernel conventions.
2. Splitting dump packet detection into separate functions for ACL
and event packets for better structure and readability.

This ensures dump packets are properly identified and consumed, avoiding
double handling and preventing NULL pointer access.
Advisories
Source ID Title
EUVD EUVD EUVD-2025-15927 In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btusb: avoid NULL pointer dereference in skb_dequeue() A NULL pointer dereference can occur in skb_dequeue() when processing a QCA firmware crash dump on WCN7851 (0489:e0f3). [ 93.672166] Bluetooth: hci0: ACL memdump size(589824) [ 93.672475] BUG: kernel NULL pointer dereference, address: 0000000000000008 [ 93.672517] Workqueue: hci0 hci_devcd_rx [bluetooth] [ 93.672598] RIP: 0010:skb_dequeue+0x50/0x80 The issue stems from handle_dump_pkt_qca() returning 0 even when a dump packet is successfully processed. This is because it incorrectly forwards the return value of hci_devcd_init() (which returns 0 on success). As a result, the caller (btusb_recv_acl_qca() or btusb_recv_evt_qca()) assumes the packet was not handled and passes it to hci_recv_frame(), leading to premature kfree() of the skb. Later, hci_devcd_rx() attempts to dequeue the same skb from the dump queue, resulting in a NULL pointer dereference. Fix this by: 1. Making handle_dump_pkt_qca() return 0 on success and negative errno on failure, consistent with kernel conventions. 2. Splitting dump packet detection into separate functions for ACL and event packets for better structure and readability. This ensures dump packets are properly identified and consumed, avoiding double handling and preventing NULL pointer access.
Ubuntu USN Ubuntu USN USN-7618-1 Linux kernel (OEM) vulnerabilities
Ubuntu USN Ubuntu USN USN-7649-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7649-2 Linux kernel (AWS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7665-1 Linux kernel (Oracle) vulnerabilities
Ubuntu USN Ubuntu USN USN-7665-2 Linux kernel (AWS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7721-1 Linux kernel (Azure) vulnerabilities
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Mon, 17 Nov 2025 17:00:00 +0000

Type Values Removed Values Added
Weaknesses CWE-476
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.15:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.15:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.15:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.15:rc4:*:*:*:*:*:*

Wed, 09 Jul 2025 02:30:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 7.0, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}


Thu, 22 May 2025 02:45:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 7.0, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

threat_severity

Moderate


Tue, 20 May 2025 15:30:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btusb: avoid NULL pointer dereference in skb_dequeue() A NULL pointer dereference can occur in skb_dequeue() when processing a QCA firmware crash dump on WCN7851 (0489:e0f3). [ 93.672166] Bluetooth: hci0: ACL memdump size(589824) [ 93.672475] BUG: kernel NULL pointer dereference, address: 0000000000000008 [ 93.672517] Workqueue: hci0 hci_devcd_rx [bluetooth] [ 93.672598] RIP: 0010:skb_dequeue+0x50/0x80 The issue stems from handle_dump_pkt_qca() returning 0 even when a dump packet is successfully processed. This is because it incorrectly forwards the return value of hci_devcd_init() (which returns 0 on success). As a result, the caller (btusb_recv_acl_qca() or btusb_recv_evt_qca()) assumes the packet was not handled and passes it to hci_recv_frame(), leading to premature kfree() of the skb. Later, hci_devcd_rx() attempts to dequeue the same skb from the dump queue, resulting in a NULL pointer dereference. Fix this by: 1. Making handle_dump_pkt_qca() return 0 on success and negative errno on failure, consistent with kernel conventions. 2. Splitting dump packet detection into separate functions for ACL and event packets for better structure and readability. This ensures dump packets are properly identified and consumed, avoiding double handling and preventing NULL pointer access.
Title Bluetooth: btusb: avoid NULL pointer dereference in skb_dequeue()
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-05-26T05:23:41.659Z

Reserved: 2025-04-16T04:51:23.968Z

Link: CVE-2025-37918

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Analyzed

Published: 2025-05-20T16:15:28.393

Modified: 2025-11-17T16:52:41.193

Link: CVE-2025-37918

cve-icon Redhat

Severity : Moderate

Publid Date: 2025-05-20T00:00:00Z

Links: CVE-2025-37918 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2025-06-27T09:26:51Z