CVE-2023-53297 Bluetooth: L2CAP: fix "bad unlock balance" in l2cap_disconnect_rsp
A race condition in the Linux kernel Bluetooth L2CAP module can cause a bad unlock balance, leading to a denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-53297?
CVE-2023-53297 is a high-severity vulnerability in Linux kernel, published on 16 Sep 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: fix "bad unlock balance" in l2cap_disconnect_rsp
conn->chan_lock isn't acquired before l2cap_get_chan_by_scid, if l2cap_get_chan_by_scid returns NULL, then 'bad unlock balance' is triggered.
Which versions are affected by CVE-2023-53297?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2023-53297?
Apply the vendor's patch.
Is CVE-2023-53297 being exploited?
There is no known exploitation of CVE-2023-53297 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2023-53297, DEBIAN-CVE-2023-53297, GHSA-r9g9-q5xh-mm5x, UBUNTU-CVE-2023-53297.