# CVE-2025-40283: Bluetooth: btusb: reorder cleanup in btusb_disconnect to avoid UAF

> A use-after-free vulnerability in the Linux kernel's Bluetooth USB driver allows attackers to potentially execute code or cause a system crash.

- **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:** 6 Dec 2025
- **Updated:** 15 Oct 2026
- **Also known as:** BELL-CVE-2025-40283, DEBIAN-CVE-2025-40283, GHSA-x57x-cxmg-52pw, ROOT-OS-DEBIAN-12-CVE-2025-40283, ROOT-OS-DEBIAN-13-CVE-2025-40283, ROOT-OS-UBUNTU-2204-CVE-2025-40283, ROOT-OS-UBUNTU-2404-CVE-2025-40283, UBUNTU-CVE-2025-40283

## What is CVE-2025-40283?

CVE-2025-40283 is a high-severity use after free vulnerability in Linux, published on 6 Dec 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:

Bluetooth: btusb: reorder cleanup in btusb_disconnect to avoid UAF

There is a KASAN: slab-use-after-free read in btusb_disconnect().
Calling "usb_driver_release_interface(&btusb_driver, data->intf)" will
free the btusb data associated with the interface. The same data is
then used later in the function, hence the UAF.

Fix by moving the accesses to btusb data to before the data is free'd.

## Which versions are affected by CVE-2025-40283?


## How do I fix CVE-2025-40283?

Apply the vendor's patch.

## Is CVE-2025-40283 being exploited?

There is no known exploitation of CVE-2025-40283 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-40283 and fix it if it is affected.

What it is: CVE-2025-40283 is a high-severity use after free vulnerability in Linux, published on 6 Dec 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-2025-40283 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-2025-40283/ (Markdown: https://insights.sbomify.com/CVE-2025-40283/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-40283
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-40283
- OSV: https://osv.dev/vulnerability/CVE-2025-40283

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-40283/
Summaries are generated and may contain mistakes; the official description above is the record.