CVE-2025-21969: Bluetooth: L2CAP: Fix slab-use-after-free Read in l2cap_send_cmd
Bluetooth: L2CAP: Fix slab-use-after-free Read in l2capsendcmd
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 6.6.85.1-2 - Upgrade
Upgrade
Linux kernel Bluetooth L2CAPto a version that resolves this vulnerability.Patch Bluetooth: L2CAP: Fix slab-use-after-free - Configuration
In the Bluetooth L2CAP/HCI interaction, add an HCI device lock to the HCI receive-data workqueue so it synchronizes correctly with the path where the hci sync command releases l2cap_conn, preventing use-after-free in l2cap_send_cmd.
Linux kernel Bluetooth Add hci dev lock to the hci receive data work queue to synchronize the two; ensure l2cap_conn lifetime is handled after hci sync releases l2cap_conn = enabled
Event History
Frequently Asked Questions
What is the severity of CVE-2025-21969?
CVE-2025-21969 is classified as a medium severity vulnerability due to the potential for exploitation through a use-after-free condition.
How do I fix CVE-2025-21969?
To fix CVE-2025-21969, update to the latest patched version of the Linux kernel that addresses this vulnerability.
Which versions of the Linux kernel are affected by CVE-2025-21969?
CVE-2025-21969 affects multiple versions of the Linux kernel prior to the application of the relevant security patches.
What are the potential impacts of CVE-2025-21969?
Exploitation of CVE-2025-21969 could lead to data corruption or system instability due to the improper handling of memory references.
Is CVE-2025-21969 remotely exploitable?
CVE-2025-21969 could potentially be exploited remotely depending on the configuration of the Bluetooth services on the affected systems.