# CVE-2022-50369: drm/vkms: Fix null-ptr-deref in vkms_release()

> A null pointer dereference in the Linux kernel's VKMS driver can cause a system crash during module initialization under low memory conditions.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **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:** Yes
- **Published:** 17 Sep 2025
- **Updated:** 11 May 2026
- **Also known as:** DEBIAN-CVE-2022-50369, GHSA-fv67-488v-7h86, UBUNTU-CVE-2022-50369

## What is CVE-2022-50369?

CVE-2022-50369 is a medium-severity vulnerability in Linux kernel, published on 17 Sep 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:

drm/vkms: Fix null-ptr-deref in vkms_release()

A null-ptr-deref is triggered when it tries to destroy the workqueue in
vkms->output.composer_workq in vkms_release().

 KASAN: null-ptr-deref in range [0x0000000000000118-0x000000000000011f]
 CPU: 5 PID: 17193 Comm: modprobe Not tainted 6.0.0-11331-gd465bff130bf #24
 RIP: 0010:destroy_workqueue+0x2f/0x710
 ...
 Call Trace:
  <TASK>
  ? vkms_config_debugfs_init+0x50/0x50 [vkms]
  __devm_drm_dev_alloc+0x15a/0x1c0 [drm]
  vkms_init+0x245/0x1000 [vkms]
  do_one_initcall+0xd0/0x4f0
  do_init_module+0x1a4/0x680
  load_module+0x6249/0x7110
  __do_sys_finit_module+0x140/0x200
  do_syscall_64+0x35/0x80
  entry_SYSCALL_64_after_hwframe+0x46/0xb0

The reason is that an OOM happened which triggers the destroy of the
workqueue, however, the workqueue is alloced in the later process,
thus a null-ptr-deref happened. A simple call graph is shown as below:

 vkms_init()
  vkms_create()
    devm_drm_dev_alloc()
      __devm_drm_dev_alloc()
        devm_drm_dev_init()
          devm_add_action_or_reset()
            devm_add_action() # an error happened
            devm_drm_dev_init_release()
              drm_dev_put()
                kref_put()
                  drm_dev_release()
                    vkms_release()
                      destroy_workqueue() # null-ptr-deref happened
    vkms_modeset_init()
      vkms_output_init()
        vkms_crtc_init() # where the workqueue get allocated

Fix this by checking if composer_workq is NULL before passing it to
the destroy_workqueue() in vkms_release().

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2022-50369?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2022-50369?

Apply the vendor's patch.

## Is CVE-2022-50369 being exploited?

There is no known exploitation of CVE-2022-50369 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-50369 and fix it if it is affected.

What it is: CVE-2022-50369 is a medium-severity vulnerability in Linux kernel, published on 17 Sep 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2022-50369 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2022-50369/ (Markdown: https://insights.sbomify.com/CVE-2022-50369/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-50369
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-50369
- OSV: https://osv.dev/vulnerability/CVE-2022-50369

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-50369/
Summaries are generated and may contain mistakes; the official description above is the record.