# CVE-2026-53384: serial: 8250_dw: unregister 8250 port if clk_notifier_register() fails

> A use-after-free vulnerability in the Linux kernel's 8250_dw serial driver allows attackers to cause denial of service or execute code if clock registration fails.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 19 Jul 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-53384, DEBIAN-CVE-2026-53384, GHSA-8qr8-6qvc-c8x9, ROOT-OS-DEBIAN-11-CVE-2026-53384, ROOT-OS-UBUNTU-2204-CVE-2026-53384, UBUNTU-CVE-2026-53384

## What is CVE-2026-53384?

CVE-2026-53384 is a critical use after free vulnerability in Linux kernel, published on 19 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

serial: 8250_dw: unregister 8250 port if clk_notifier_register() fails

dw8250_probe() registers the 8250 port via serial8250_register_8250_port()
and then, if the device has a clock, registers a clock notifier. If
clk_notifier_register() fails, probe returns the error but leaves the
8250 port registered. The matching serial8250_unregister_port() lives
in dw8250_remove(), which is not called when probe fails, so the port
slot stays occupied until the device is rebound or the system is
rebooted. The devm-allocated driver data is freed while the port still
references it (via the saved private_data and serial_in/serial_out
callbacks), so any access to that port slot before a rebind is a
use-after-free hazard.

Unregister the port on the clk_notifier_register() error path.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2026-53384?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-53384?

Apply the vendor's patch.

## Is CVE-2026-53384 being exploited?

There is no known exploitation of CVE-2026-53384 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-2026-53384 and fix it if it is affected.

What it is: CVE-2026-53384 is a critical use after free vulnerability in Linux kernel, published on 19 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-53384 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-2026-53384/ (Markdown: https://insights.sbomify.com/CVE-2026-53384/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-53384
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-53384
- OSV: https://osv.dev/vulnerability/CVE-2026-53384

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-53384/
Summaries are generated and may contain mistakes; the official description above is the record.