CVE-2026-89446 iommufd: Release current IOAS on xa_store() failure
A local attacker can cause a resource leak in the Linux kernel iommufd subsystem by triggering a specific error path, leading to 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-2026-89446?
CVE-2026-89446 is a denial of service vulnerability in Linux, published on 11 Sep 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:
iommufd: Release current IOAS on xa_store() failure
iommufd_take_all_iova_rwsem() takes an object reference and the iova_rwsem write lock before storing the IOAS in the temporary ioas_list xarray.
If xa_store() fails, the current IOAS has not been inserted into ioas_list yet. iommufd_release_all_iova_rwsem() only unwinds IOAS objects already present in that xarray, so it cannot release the current IOAS.
Release the current IOAS rwsem and object reference before unwinding the previously stored entries.
Which versions are affected by CVE-2026-89446?
How do I fix CVE-2026-89446?
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-2026-89446 being exploited?
There is no known exploitation of CVE-2026-89446 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-89446, DEBIAN-CVE-2026-89446, GHSA-9fjc-q922-2qfq, UBUNTU-CVE-2026-89446.