# CVE-2026-31583: media: em28xx: fix use-after-free in em28xx_v4l2_open()

> A race condition in the em28xx video driver allows use-after-free and null dereference, potentially causing crashes or code execution.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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:** 24 Apr 2026
- **Updated:** 15 Oct 2026
- **Also known as:** AZL-83666, BELL-CVE-2026-31583, DEBIAN-CVE-2026-31583, GHSA-2hvg-8mmr-f5mc, ROOT-OS-DEBIAN-11-CVE-2026-31583, ROOT-OS-DEBIAN-12-CVE-2026-31583, ROOT-OS-DEBIAN-13-CVE-2026-31583, ROOT-OS-UBUNTU-2204-CVE-2026-31583, ROOT-OS-UBUNTU-2404-CVE-2026-31583, UBUNTU-CVE-2026-31583

## What is CVE-2026-31583?

CVE-2026-31583 is a high-severity use after free vulnerability in Linux kernel, published on 24 Apr 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:

media: em28xx: fix use-after-free in em28xx_v4l2_open()

em28xx_v4l2_open() reads dev->v4l2 without holding dev->lock,
creating a race with em28xx_v4l2_init()'s error path and
em28xx_v4l2_fini(), both of which free the em28xx_v4l2 struct
and set dev->v4l2 to NULL under dev->lock.

This race leads to two issues:
 - use-after-free in v4l2_fh_init() when accessing vdev->ctrl_handler,
   since the video_device is embedded in the freed em28xx_v4l2 struct.
 - NULL pointer dereference in em28xx_resolution_set() when accessing
   v4l2->norm, since dev->v4l2 has been set to NULL.

Fix this by moving the mutex_lock() before the dev->v4l2 read and
adding a NULL check for dev->v4l2 under the lock.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2026-31583?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-31583?

Apply the vendor's patch.

## Is CVE-2026-31583 being exploited?

There is no known exploitation of CVE-2026-31583 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-2026-31583 and fix it if it is affected.

What it is: CVE-2026-31583 is a high-severity use after free vulnerability in Linux kernel, published on 24 Apr 2026. 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-2026-31583 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-2026-31583/ (Markdown: https://insights.sbomify.com/CVE-2026-31583/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-31583
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-31583
- OSV: https://osv.dev/vulnerability/CVE-2026-31583

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-31583/
Summaries are generated and may contain mistakes; the official description above is the record.