# CVE-2026-74302: Bluetooth: hci_core: Fix UAF in hci_unregister_dev()

> A use-after-free in the Linux kernel Bluetooth subsystem allows attackers to execute arbitrary code or escalate privileges 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:** 15 Aug 2026
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-96477, BELL-CVE-2026-74302, DEBIAN-CVE-2026-74302, GHSA-78xg-w78v-wc27, UBUNTU-CVE-2026-74302

## What is CVE-2026-74302?

CVE-2026-74302 is a high-severity use after free vulnerability in Linux, published on 15 Aug 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:

Bluetooth: hci_core: Fix UAF in hci_unregister_dev()

hci_unregister_dev() does not disable cmd_timer and ncmd_timer
before the hci_dev structure is freed. If a timeout fires
during device teardown, the callback dereferences freed memory
(including the hdev->reset function pointer), leading to a
use-after-free.

Add disable_delayed_work_sync() calls alongside the existing
disable_work_sync() calls to ensure both timers are fully
quiesced before teardown proceeds.

## Which versions are affected by CVE-2026-74302?


## How do I fix CVE-2026-74302?

Apply the vendor's patch.

## Is CVE-2026-74302 being exploited?

There is no known exploitation of CVE-2026-74302 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-74302 and fix it if it is affected.

What it is: CVE-2026-74302 is a high-severity use after free vulnerability in Linux, published on 15 Aug 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-2026-74302 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-2026-74302/ (Markdown: https://insights.sbomify.com/CVE-2026-74302/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-74302
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-74302
- OSV: https://osv.dev/vulnerability/CVE-2026-74302

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-74302/
Summaries are generated and may contain mistakes; the official description above is the record.