# CVE-2023-54210: Bluetooth: hci_sync: Avoid use-after-free in dbg for hci_remove_adv_monitor()

> A use-after-free vulnerability in the Linux kernel's Bluetooth HCI subsystem allows attackers to cause a denial of service or potentially execute code.

- **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:** 30 Dec 2025
- **Updated:** 15 Oct 2026
- **Also known as:** BELL-CVE-2023-54210, DEBIAN-CVE-2023-54210, GHSA-58q4-73m8-4p8p, UBUNTU-CVE-2023-54210

## What is CVE-2023-54210?

CVE-2023-54210 is a high-severity use after free vulnerability in Linux, published on 30 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: hci_sync: Avoid use-after-free in dbg for hci_remove_adv_monitor()

KASAN reports that there's a use-after-free in
hci_remove_adv_monitor(). Trawling through the disassembly, you can
see that the complaint is from the access in bt_dev_dbg() under the
HCI_ADV_MONITOR_EXT_MSFT case. The problem case happens because
msft_remove_monitor() can end up freeing the monitor
structure. Specifically:
  hci_remove_adv_monitor() ->
  msft_remove_monitor() ->
  msft_remove_monitor_sync() ->
  msft_le_cancel_monitor_advertisement_cb() ->
  hci_free_adv_monitor()

Let's fix the problem by just stashing the relevant data when it's
still valid.

## Which versions are affected by CVE-2023-54210?


## How do I fix CVE-2023-54210?

Apply the vendor's patch.

## Is CVE-2023-54210 being exploited?

There is no known exploitation of CVE-2023-54210 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-54210 and fix it if it is affected.

What it is: CVE-2023-54210 is a high-severity use after free vulnerability in Linux, published on 30 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-2023-54210 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-2023-54210/ (Markdown: https://insights.sbomify.com/CVE-2023-54210/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-54210
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-54210
- OSV: https://osv.dev/vulnerability/CVE-2023-54210

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-54210/
Summaries are generated and may contain mistakes; the official description above is the record.