CVE-2026-43007 accel/qaic: Handle DBC deactivation if the owner went away
A race condition in the Linux kernel QAIC driver causes a hang when a device deactivation transaction arrives after the user process exits, requiring a kernel patch.
- 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-2026-43007?
CVE-2026-43007 is a high-severity denial of service vulnerability in Linux kernel, published on 1 May 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:
accel/qaic: Handle DBC deactivation if the owner went away
When a DBC is released, the device sends a QAIC_TRANS_DEACTIVATE_FROM_DEV transaction to the host over the QAIC_CONTROL MHI channel. QAIC handles this by calling decode_deactivate() to release the resources allocated for that DBC. Since that handling is done in the qaic_manage_ioctl() context, if the user goes away before receiving and handling the deactivation, the host will be out-of-sync with the DBCs available for use, and the DBC resources will not be freed unless the device is removed. If another user loads and requests to activate a network, then the device assigns the same DBC to that network, QAIC will "indefinitely" wait for dbc->in_use = false, leading the user process to hang.
As a solution to this, handle QAIC_TRANS_DEACTIVATE_FROM_DEV transactions that are received after the user has gone away.
Weakness: CWE-415
Which versions are affected by CVE-2026-43007?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-43007?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-43007 being exploited?
There is no known exploitation of CVE-2026-43007 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-43007, DEBIAN-CVE-2026-43007, GHSA-cw7c-wp8j-jm6j, ROOT-OS-UBUNTU-2404-CVE-2026-43007, UBUNTU-CVE-2026-43007.