# CVE-2026-89893: media: cx23885: cancel NetUP CI work before teardown

> A use-after-free vulnerability in the Linux kernel cx23885 driver allows attackers to cause denial of service or execute code via race conditions during device teardown.

- **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:** 16 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-101516, BELL-CVE-2026-89893, DEBIAN-CVE-2026-89893, GHSA-8263-vr49-mgcg, UBUNTU-CVE-2026-89893

## What is CVE-2026-89893?

CVE-2026-89893 is a high-severity use after free vulnerability in Linux, published on 16 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:

media: cx23885: cancel NetUP CI work before teardown

netup_ci_exit() frees a netup_ci_state while its work item,
netup_read_ci_status(), may still be pending or running on the system
workqueue. The worker obtains the state with container_of() and
dereferences it, so it must not outlive the state.

netup_ci_init() queues the initial status read, and CI GPIO interrupts
subsequently queue the same work from netup_ci_slot_status(). During
remove, cx23885_finidev() calls free_irq() before the CI device is
unregistered. free_irq() prevents further IRQ handlers from running,
but does not drain work queued previously, so the worker can run after
netup_ci_exit() frees the state.

Call cancel_work_sync() before dvb_ca_en50221_release() and kfree().

This issue was found by an in-house static analysis tool.

## Which versions are affected by CVE-2026-89893?


## How do I fix CVE-2026-89893?

Apply the vendor's patch.

## Is CVE-2026-89893 being exploited?

There is no known exploitation of CVE-2026-89893 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-89893 and fix it if it is affected.

What it is: CVE-2026-89893 is a high-severity use after free vulnerability in Linux, published on 16 Sep 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-2026-89893 in the wild and no public exploit code.

Affected product: Linux. 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-2026-89893/ (Markdown: https://insights.sbomify.com/CVE-2026-89893/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-89893
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-89893
- OSV: https://osv.dev/vulnerability/CVE-2026-89893

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-89893/
Summaries are generated and may contain mistakes; the official description above is the record.