# CVE-2024-27000: serial: mxs-auart: add spinlock around changing cts state

> A missing spinlock in the mxs-auart serial driver causes a race condition, leading to kernel warnings and potential system instability on affected hardware.

- **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:** 1 May 2024
- **Updated:** 11 May 2026
- **Also known as:** AZL-40454, BELL-CVE-2024-27000, DEBIAN-CVE-2024-27000, GHSA-pxvx-632v-2p4v, UBUNTU-CVE-2024-27000

## What is CVE-2024-27000?

CVE-2024-27000 is a high-severity vulnerability in Debian Debian Linux, published on 1 May 2024. 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:

serial: mxs-auart: add spinlock around changing cts state

The uart_handle_cts_change() function in serial_core expects the caller
to hold uport->lock. For example, I have seen the below kernel splat,
when the Bluetooth driver is loaded on an i.MX28 board.

    [   85.119255] ------------[ cut here ]------------
    [   85.124413] WARNING: CPU: 0 PID: 27 at /drivers/tty/serial/serial_core.c:3453 uart_handle_cts_change+0xb4/0xec
    [   85.134694] Modules linked in: hci_uart bluetooth ecdh_generic ecc wlcore_sdio configfs
    [   85.143314] CPU: 0 PID: 27 Comm: kworker/u3:0 Not tainted 6.6.3-00021-gd62a2f068f92 #1
    [   85.151396] Hardware name: Freescale MXS (Device Tree)
    [   85.156679] Workqueue: hci0 hci_power_on [bluetooth]
    (...)
    [   85.191765]  uart_handle_cts_change from mxs_auart_irq_handle+0x380/0x3f4
    [   85.198787]  mxs_auart_irq_handle from __handle_irq_event_percpu+0x88/0x210
    (...)

## Which versions are affected by CVE-2024-27000?

It affects 3 products.


Products: Debian Debian Linux, Fedoraproject Fedora, Linux kernel.

## How do I fix CVE-2024-27000?

Apply the vendor's patch.

## Is CVE-2024-27000 being exploited?

There is no known exploitation of CVE-2024-27000 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

- [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild)
- [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-27000 and fix it if it is affected.

What it is: CVE-2024-27000 is a high-severity vulnerability in Debian Debian Linux, published on 1 May 2024. 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-2024-27000 in the wild and no public exploit code.

Affected product: Debian Debian 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-2024-27000/ (Markdown: https://insights.sbomify.com/CVE-2024-27000/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-27000
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-27000
- OSV: https://osv.dev/vulnerability/CVE-2024-27000

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-27000/
Summaries are generated and may contain mistakes; the official description above is the record.