CVE Catalog

CVE-2025-68304

HighCVSS 8.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.21%

12th percentile - higher than 12% of all known CVEs

Summary

A use-after-free (UAF) vulnerability was found in the Linux kernel's Bluetooth stack in the packet RX path. Improper locking when looking up the hci_conn structure allows concurrent modification or deletion, potentially causing a system crash.

Risk Assessment

An attacker could exploit this vulnerability to cause a kernel panic by sending specially crafted Bluetooth packets, leading to a denial of service (DoS).

Recommendation

Immediately update the Linux kernel to a version containing the fix (commit 5af1f84ed13a or later). If an update is not possible, consider disabling the Bluetooth stack on the system.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

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)

Vulnerability data from NVD (NIST) · CISA KEV · EPSS