# CVE-2026-53358: Bluetooth: L2CAP: use chan timer to close channels in cleanup_listen()

> A race condition in the Linux kernel Bluetooth L2CAP subsystem can lead to a denial of service due to improper lock ordering during channel cleanup.

- **Severity:** High 8.8 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **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:** 2 Jul 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-53358, DEBIAN-CVE-2026-53358, GHSA-g5v6-wm74-gh57, ROOT-OS-DEBIAN-11-CVE-2026-53358, ROOT-OS-DEBIAN-12-CVE-2026-53358, ROOT-OS-UBUNTU-2204-CVE-2026-53358, ROOT-OS-UBUNTU-2404-CVE-2026-53358, UBUNTU-CVE-2026-53358

## What is CVE-2026-53358?

CVE-2026-53358 is a high-severity vulnerability in Linux kernel, published on 2 Jul 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: L2CAP: use chan timer to close channels in cleanup_listen()

l2cap_chan_close() removes the channel from conn->chan_l, which
must be done under conn->lock.  cleanup_listen() runs under the
parent sk_lock, so acquiring conn->lock would invert the
established conn->lock -> chan->lock -> sk_lock order.

Instead of calling l2cap_chan_close() directly, schedule
l2cap_chan_timeout with delay 0 to close the channel
asynchronously.  The timeout handler already acquires conn->lock
and chan->lock in the correct order.

The timer is only armed when chan->conn is still set: if it is
already NULL, l2cap_conn_del() has already processed this channel
(l2cap_chan_del + l2cap_sock_teardown_cb + l2cap_sock_close_cb),
so there is nothing left to do.  If l2cap_conn_del() races in
after the timer is armed, __clear_chan_timer() inside
l2cap_chan_del() cancels it; if the timer has already fired, the
handler returns harmlessly because chan->conn was cleared.

Weakness: CWE-667 (Improper Locking), CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization)

## Which versions are affected by CVE-2026-53358?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-53358?

Apply the vendor's patch.

## Is CVE-2026-53358 being exploited?

There is no known exploitation of CVE-2026-53358 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-53358 and fix it if it is affected.

What it is: CVE-2026-53358 is a high-severity vulnerability in Linux kernel, published on 2 Jul 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-2026-53358 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2026-53358/ (Markdown: https://insights.sbomify.com/CVE-2026-53358/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-53358
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-53358
- OSV: https://osv.dev/vulnerability/CVE-2026-53358

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-53358/
Summaries are generated and may contain mistakes; the official description above is the record.