CVE-2026-98689 thunderbolt: Don't access a DP tunnel after its DPRX read was canceled
A race condition in the Linux kernel Thunderbolt driver allows accessing a torn-down DP tunnel, potentially causing a system crash during suspend.
- 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-2026-98689?
CVE-2026-98689 is a vulnerability in Linux, published on 18 Oct 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:
thunderbolt: Don't access a DP tunnel after its DPRX read was canceled
tb_dp_dprx_work() checks ->dprx_canceled before it takes tb->lock so it misses a tb_dp_dprx_stop() that could not cancel the already running work. It then polls the DPRX capabilities and runs the callback for a tunnel that has already been torn down while the domain is suspending or going away.
This can be hit by cancelling the DPRX read from outside the ordered tb->wq: During suspend tb_disconnect_and_release_dp() does just this and with a later patch tb_stop() will do it as well. The latter in combination with the Apple NHI where the DPRX read never completed is how I hit this.
Check the flag with tb->lock held instead and check it again in tb_dp_tunnel_active() because the callback runs after the lock has been dropped again.
Also clear the flag in tb_dp_dprx_start() so that it only ever describes the work that is currently in flight.
Which versions are affected by CVE-2026-98689?
How do I fix CVE-2026-98689?
Apply the vendor's patch.
Is CVE-2026-98689 being exploited?
There is no known exploitation of CVE-2026-98689 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-98689, DEBIAN-CVE-2026-98689, GHSA-8x4h-8gwm-w6jp, UBUNTU-CVE-2026-98689.