cbcvebase.
CVE-2025-68304
published 2025-12-16

CVE-2025-68304: In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_core: lookup hci_conn on RX path on protocol side The hdev…

PriorityP344high8.8CVSS 3.1
AVAACLPRNUINSUCHIHAH
EPSS
0.21%
11.8th percentile
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_core: lookup hci_conn on RX path on protocol side The hdev lock/lookup/unlock/use pattern in the packet RX path doesn't ensure hci_conn* is not concurrently modified/deleted. This locking appears to be leftover from before conn_hash started using RCU commit bf4c63252490b ("Bluetooth: convert conn hash to RCU") and not clear if it had purpose since then. Currently, there are code paths that delete hci_conn* from elsewhere than the ordered hdev->workqueue where the RX work runs in. E.g. commit 5af1f84ed13a ("Bluetooth: hci_sync: Fix UAF on hci_abort_conn_sync") introduced some of these, and there probably were a few others before it. It's better to do the locking so that even if these run concurrently no UAF is possible. Move the lookup of hci_conn and associated socket-specific conn to protocol recv handlers, and do them within a single critical section to cover hci_conn* usage and lookup. syzkaller has reported a crash that appears to be this issue: [Task hdev->workqueue] [Task 2] hci_disconnect_all_sync l2cap_recv_acldata(hcon) hci_conn_get(hcon) hci_abort_conn_sync(hcon) hci_dev_lock hci_dev_lock hci_conn_del(hcon) v-------------------------------- hci_dev_unlock hci_conn_put(hcon) conn = hcon->l2cap_data (UAF)

Affected

19 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.17.11-1 (forky)linux 6.17.11-1 (forky)
linuxlinux
linuxlinux
linuxlinux
linuxlinux
linuxlinux>= 5af1f84ed13a416297ab9ced7537f4d5ae7f329a < ec74cdf77310c43b01b83ee898a9bd4b4b0b8e93ec74cdf77310c43b01b83ee898a9bd4b4b0b8e93
linuxlinux>= 5af1f84ed13a416297ab9ced7537f4d5ae7f329a < 79a2d4678ba90bdba577dc3af88cc900d6dcd5ee79a2d4678ba90bdba577dc3af88cc900d6dcd5ee
linuxlinux>= 6.1.149 < 6.26.2
linuxlinux>= 6.4.16 < 6.56.5
linuxlinux>= 6.5.3 < 6.66.6
linuxlinux_kernel>= 0 < 6.17.11-16.17.11-1
linuxlinux_kernel>= 0 < 6.17.0-19.196.17.0-19.19
linuxlinux_kernel>= 6.6.0 < 6.17.116.17.11
msrcazl3_kernel_6.6.117.1-1_on_azure_linux_3.0
msrcazl3_kernel_6.6.119.3-1_on_azure_linux_3.0
msrcazl3_kernel_6.6.119.3-3_on_azure_linux_3.0
msrcazl3_kernel_6.6.121.1-1_on_azure_linux_3.0
msrcazl3_kernel_6.6.126.1-1_on_azure_linux_3.0
msrcazl3_kernel_6.6.130.1-3_on_azure_linux_3.0

CVSS provenance

nvdv3.18.8HIGHCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
osv7.2HIGH
vendor_ubuntu7.2HIGH
vendor_msrc7.0HIGH
vendor_redhat5.5MEDIUM
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