CVE-2026-89741 Revert "media: v4l2-dev: fix error handling in __video_register_device()"

What is CVE-2026-89741?

CVE-2026-89741 is a high-severity use after free 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:

Revert "media: v4l2-dev: fix error handling in __video_register_device()"

This reverts commit 2a934fdb01db6458288fc9386d3d8ceba6dd551a.

The intentions of that patch were good, but it doesn't work.

The idea is that if device_register fails, you have to do a put_device to let the ref counter release resources.

However, the V4L2 API says that if video_register_device() fails, then you have to call video_device_release(), which kfree()s the video_device struct.

But the put_device() will already have freed the struct, so you end up in a double-free scenario.

There is not really a good way of fixing this without breaking video_register_device() into two parts, one that initializes everything, and one that does the actual device_register, and then converting all V4L2 drivers to this new model.

That is a massive job, and it is very unlikely that device_register will fail.

So rather than ending up in a double-free scenario, just revert this patch, and in that case we'll have a small memory leak. Which is a lot more robust.

Which versions are affected by CVE-2026-89741?

How do I fix CVE-2026-89741?

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-2026-89741 being exploited?

There is no known exploitation of CVE-2026-89741 in the wild and no public exploit code.

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as AZL-100433, BELL-CVE-2026-89741, DEBIAN-CVE-2026-89741, GHSA-x4c4-qfr2-c3vv, UBUNTU-CVE-2026-89741.