# CVE-2025-37967: usb: typec: ucsi: displayport: Fix deadlock

> A deadlock in the Linux kernel UCSI driver can cause a denial of service when handling DisplayPort connections.

- **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:** 20 May 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2025-37967, DEBIAN-CVE-2025-37967, GHSA-w939-6x76-94vc, ROOT-OS-DEBIAN-11-CVE-2025-37967, ROOT-OS-DEBIAN-12-CVE-2025-37967, ROOT-OS-UBUNTU-2204-CVE-2025-37967, ROOT-OS-UBUNTU-2404-CVE-2025-37967, UBUNTU-CVE-2025-37967

## What is CVE-2025-37967?

CVE-2025-37967 is a medium-severity vulnerability in Debian Debian Linux, published on 20 May 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:

usb: typec: ucsi: displayport: Fix deadlock

This patch introduces the ucsi_con_mutex_lock / ucsi_con_mutex_unlock
functions to the UCSI driver. ucsi_con_mutex_lock ensures the connector
mutex is only locked if a connection is established and the partner pointer
is valid. This resolves a deadlock scenario where
ucsi_displayport_remove_partner holds con->mutex waiting for
dp_altmode_work to complete while dp_altmode_work attempts to acquire it.

Weakness: CWE-667 (Improper Locking)

## Which versions are affected by CVE-2025-37967?

It affects 2 products.


Products: Debian Debian Linux, Linux kernel.

## How do I fix CVE-2025-37967?

Apply the vendor's patch.

## Is CVE-2025-37967 being exploited?

There is no known exploitation of CVE-2025-37967 in the wild and no public exploit code.

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- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-37967 and fix it if it is affected.

What it is: CVE-2025-37967 is a medium-severity vulnerability in Debian Debian Linux, published on 20 May 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-2025-37967 in the wild and no public exploit code.

Affected product: Debian Debian 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-2025-37967/ (Markdown: https://insights.sbomify.com/CVE-2025-37967/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-37967
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-37967
- OSV: https://osv.dev/vulnerability/CVE-2025-37967

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-37967/
Summaries are generated and may contain mistakes; the official description above is the record.