# CVE-2025-40213: Bluetooth: MGMT: fix crash in set_mesh_sync and set_mesh_complete

> A memory corruption flaw in the Linux kernel Bluetooth subsystem allows attackers to cause a system crash via stack-out-of-bounds writes.

- **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:** 24 Nov 2025
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-89667, BELL-CVE-2025-40213, DEBIAN-CVE-2025-40213, GHSA-hxj9-5m9x-pxq2, ROOT-OS-DEBIAN-13-CVE-2025-40213, UBUNTU-CVE-2025-40213

## What is CVE-2025-40213?

CVE-2025-40213 is a high-severity memory corruption vulnerability in Linux, published on 24 Nov 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: MGMT: fix crash in set_mesh_sync and set_mesh_complete

There is a BUG: KASAN: stack-out-of-bounds in set_mesh_sync due to
memcpy from badly declared on-stack flexible array.

Another crash is in set_mesh_complete() due to double list_del via
mgmt_pending_valid + mgmt_pending_remove.

Use DEFINE_FLEX to declare the flexible array right, and don't memcpy
outside bounds.

As mgmt_pending_valid removes the cmd from list, use mgmt_pending_free,
and also report status on error.

## Which versions are affected by CVE-2025-40213?


## How do I fix CVE-2025-40213?

Apply the vendor's patch.

## Is CVE-2025-40213 being exploited?

There is no known exploitation of CVE-2025-40213 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-40213 and fix it if it is affected.

What it is: CVE-2025-40213 is a high-severity memory corruption vulnerability in Linux, published on 24 Nov 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-2025-40213 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-2025-40213/ (Markdown: https://insights.sbomify.com/CVE-2025-40213/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-40213
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-40213
- OSV: https://osv.dev/vulnerability/CVE-2025-40213

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-40213/
Summaries are generated and may contain mistakes; the official description above is the record.