CVE-2026-45989 of: unittest: fix use-after-free in testdrv_probe()
A use-after-free in the Linux kernel's device tree unit test driver allows attackers to potentially execute code or escalate privileges.
- 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-2026-45989?
CVE-2026-45989 is a high-severity use after free vulnerability in Linux kernel, published on 27 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:
of: unittest: fix use-after-free in testdrv_probe()
The function testdrv_probe() retrieves the device_node from the PCI device, applies an overlay, and then immediately calls of_node_put(dn). This releases the reference held by the PCI core, potentially freeing the node if the reference count drops to zero. Later, the same freed pointer 'dn' is passed to of_platform_default_populate(), leading to a use-after-free.
The reference to pdev->dev.of_node is owned by the device model and should not be released by the driver. Remove the erroneous of_node_put() to prevent premature freeing.
Weakness: CWE-416
Which versions are affected by CVE-2026-45989?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-45989?
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-2026-45989 being exploited?
There is no known exploitation of CVE-2026-45989 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-88707, BELL-CVE-2026-45989, DEBIAN-CVE-2026-45989, GHSA-26rf-29mw-gf9h, ROOT-OS-UBUNTU-2404-CVE-2026-45989, UBUNTU-CVE-2026-45989.