# CVE-2026-98297: Bluetooth: hci_core: Fix queuing tx_work after workqueue is drained

> A race condition in the Linux kernel Bluetooth subsystem can cause a kernel warning and drop work, leading to a denial of service.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 6 Oct 2026
- **Updated:** 21 Oct 2026
- **Also known as:** BELL-CVE-2026-98297, DEBIAN-CVE-2026-98297, GHSA-mvfp-xjr6-rmvq, UBUNTU-CVE-2026-98297

## What is CVE-2026-98297?

CVE-2026-98297 is a vulnerability in Linux, published on 6 Oct 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 queuing tx_work after workqueue is drained

hci_send_acl(), hci_send_sco() and hci_send_iso() queue hdev->tx_work
unconditionally. They can run from the L2CAP/SCO/ISO socket send path
while hci_dev_close_sync() is draining hdev->workqueue (HCIDEVDOWN
racing with a socket write). Since that queue_work() is not chained
work from the tx_work worker itself, __queue_work() sees the queue
marked __WQ_DRAINING, warns "cannot queue %ps on wq %s", and drops
the work:

  WARNING: CPU: 1 PID: 5985 at kernel/workqueue.c:2352 __queue_work
  Call Trace:
   queue_work_on
   l2cap_chan_send
   l2cap_sock_sendmsg
   ...

hci_dev_close_sync() already sets HCI_CMD_DRAIN_WORKQUEUE before
draining, but only hci_cmd_work() and handle_cmd_cnt_and_timer()
check it before queuing. Route the tx_work producers through the
same guard via a shared hci_sched_tx() helper.

## Which versions are affected by CVE-2026-98297?


## How do I fix CVE-2026-98297?

Apply the vendor's patch.

## Is CVE-2026-98297 being exploited?

There is no known exploitation of CVE-2026-98297 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98297 and fix it if it is affected.

What it is: CVE-2026-98297 is a vulnerability in Linux, published on 6 Oct 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-2026-98297 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-2026-98297/ (Markdown: https://insights.sbomify.com/CVE-2026-98297/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98297
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98297
- OSV: https://osv.dev/vulnerability/CVE-2026-98297

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98297/
Summaries are generated and may contain mistakes; the official description above is the record.