CVE Catalog

CVE-2026-90256

HighCVSS 8.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.29%

22th percentile - higher than 22% of all known CVEs

Summary

In the Linux kernel, in Bluetooth L2CAP, the hci_conn::l2cap_data field is accessed without locks in l2cap_disconn_ind, potentially leading to use-after-free if l2cap_conn is deleted concurrently. The fix uses proto_lock to guard l2cap_data.

Risk Assessment

Possible system crash or remote code execution due to use-after-free in the Bluetooth stack.

Recommendation

Install the updated Linux kernel with this fix to protect against the UAF bug in L2CAP.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: use proto_lock for l2cap_data to fix l2cap_disconn_ind hci_conn::l2cap_data is accessed without locks in l2cap_disconn_ind via hci_conn_timeout (disc_work) -> hci_proto_disconn_ind -> l2cap_disconn_ind. This is UAF if the l2cap_conn is deleted concurrently. disc_work is disabled sync in hci_conn_del(), so we cannot take hci_dev_lock in disc_work. Fix by using proto_lock to guard l2cap_data, in addition to hdev->lock which is held in other access paths.

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