CVE-2026-90256 and is rated High severity with a CVSS score of 8.8. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
CISA KEVNot listedBased on the latest collected catalog
EPSS0.4%Estimated 30-day exploitation probability
Ransomware useNot markedCISA KEV ransomware field
Threat actors0Source-linked actor relationships
Overview
What is CVE-2026-90256?
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.