# CVE-2026-31499: Bluetooth: L2CAP: Fix deadlock in l2cap_conn_del()

> A deadlock in the Linux kernel Bluetooth L2CAP module can cause a system hang, requiring a kernel patch to resolve.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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:** 22 Apr 2026
- **Updated:** 23 May 2026
- **Also known as:** AZL-85008, BELL-CVE-2026-31499, DEBIAN-CVE-2026-31499, GHSA-hr22-g233-2gjg, ROOT-OS-DEBIAN-13-CVE-2026-31499, ROOT-OS-UBUNTU-2404-CVE-2026-31499, UBUNTU-CVE-2026-31499

## What is CVE-2026-31499?

CVE-2026-31499 is a medium-severity vulnerability in Linux kernel, published on 22 Apr 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: Fix deadlock in l2cap_conn_del()

l2cap_conn_del() calls cancel_delayed_work_sync() for both info_timer
and id_addr_timer while holding conn->lock. However, the work functions
l2cap_info_timeout() and l2cap_conn_update_id_addr() both acquire
conn->lock, creating a potential AB-BA deadlock if the work is already
executing when l2cap_conn_del() takes the lock.

Move the work cancellations before acquiring conn->lock and use
disable_delayed_work_sync() to additionally prevent the works from
being rearmed after cancellation, consistent with the pattern used in
hci_conn_del().

Weakness: CWE-667 (Improper Locking)

## Which versions are affected by CVE-2026-31499?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-31499?

Apply the vendor's patch.

## Is CVE-2026-31499 being exploited?

There is no known exploitation of CVE-2026-31499 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-2026-31499 and fix it if it is affected.

What it is: CVE-2026-31499 is a medium-severity vulnerability in Linux kernel, published on 22 Apr 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-2026-31499 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-2026-31499/ (Markdown: https://insights.sbomify.com/CVE-2026-31499/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-31499
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-31499
- OSV: https://osv.dev/vulnerability/CVE-2026-31499

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-31499/
Summaries are generated and may contain mistakes; the official description above is the record.