CVE-2025-68298 Bluetooth: btusb: mediatek: Avoid btusb_mtk_claim_iso_intf() NULL deref
A NULL pointer dereference in the Linux kernel Bluetooth driver allows local attackers to cause a system crash via specific USB interactions.
- 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-2025-68298?
CVE-2025-68298 is a vulnerability in Linux, published on 16 Dec 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: btusb: mediatek: Avoid btusb_mtk_claim_iso_intf() NULL deref
In btusb_mtk_setup(), we set `btmtk_data->isopkt_intf` to: usb_ifnum_to_if(data->udev, MTK_ISO_IFNUM)
That function can return NULL in some cases. Even when it returns NULL, though, we still go on to call btusb_mtk_claim_iso_intf().
As of commit e9087e828827 ("Bluetooth: btusb: mediatek: Add locks for usb_driver_claim_interface()"), calling btusb_mtk_claim_iso_intf() when `btmtk_data->isopkt_intf` is NULL will cause a crash because we'll end up passing a bad pointer to device_lock(). Prior to that commit we'd pass the NULL pointer directly to usb_driver_claim_interface() which would detect it and return an error, which was handled.
Resolve the crash in btusb_mtk_claim_iso_intf() by adding a NULL check at the start of the function. This makes the code handle a NULL `btmtk_data->isopkt_intf` the same way it did before the problematic commit (just with a slight change to the error message printed).
Which versions are affected by CVE-2025-68298?
How do I fix CVE-2025-68298?
Apply the vendor's patch.
Is CVE-2025-68298 being exploited?
There is no known exploitation of CVE-2025-68298 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2025-68298, DEBIAN-CVE-2025-68298, GHSA-f9r4-fv84-3cgc, UBUNTU-CVE-2025-68298.