CVE-2026-68389 Bluetooth: hci_qca: Clear memdump state on invalid dump size
A use-after-free vulnerability in the Linux kernel Bluetooth driver allows attackers to cause denial of service or execute arbitrary code via malformed dump sizes.
- 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-2026-68389?
CVE-2026-68389 is a high-severity use after free vulnerability in Linux, published on 10 Aug 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: hci_qca: Clear memdump state on invalid dump size
qca_controller_memdump() allocates qca->qca_memdump before processing the first dump packet. For a sequence-zero packet it then disables IBS, marks memdump collection active, and reads the advertised dump size.
If the controller reports a zero dump size, the error path frees the local qca_memdump object and returns without clearing qca->qca_memdump or undoing the collection state. A later memdump work item initializes its local pointer from qca->qca_memdump and skips allocation when that pointer is non-NULL, so it can operate on freed memory. The stale collection and IBS-disabled flags can also leave waiters or later transmit handling blocked behind an aborted dump.
Clear the saved pointer and memdump state before returning from the invalid-size path, matching the cleanup used when hci_devcd_init() fails.
A static analysis checker reported the stale memdump state, and manual source review confirmed the invalid-size failure path.
Which versions are affected by CVE-2026-68389?
How do I fix CVE-2026-68389?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-68389 being exploited?
There is no known exploitation of CVE-2026-68389 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-68389, DEBIAN-CVE-2026-68389, GHSA-ghf3-w254-j47x, UBUNTU-CVE-2026-68389.