CVE-2026-53251 Bluetooth: ISO: Fix not releasing hdev reference on iso_conn_big_sync
A missing reference release in the Linux kernel Bluetooth ISO subsystem can lead to resource leaks and potential denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-53251?
CVE-2026-53251 is a medium-severity memory corruption vulnerability in Linux kernel, published on 25 Jun 2026. 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: ISO: Fix not releasing hdev reference on iso_conn_big_sync
hci_get_route() returns a reference-counted hci_dev pointer via hci_dev_hold(). The function exits normally or with an error without ever releasing it.
Weakness: CWE-772
Which versions are affected by CVE-2026-53251?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-53251?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-53251 being exploited?
There is no known exploitation of CVE-2026-53251 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-53251, DEBIAN-CVE-2026-53251, GHSA-q6x9-g333-77r4, ROOT-OS-UBUNTU-2404-CVE-2026-53251, UBUNTU-CVE-2026-53251.