# CVE-2025-38174: thunderbolt: Do not double dequeue a configuration request

> A double dequeue bug in the Linux kernel Thunderbolt driver causes a general protection fault, leading to system crashes.

- **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:** 4 Jul 2025
- **Updated:** 5 Aug 2026
- **Also known as:** AZL-64647, BELL-CVE-2025-38174, DEBIAN-CVE-2025-38174, GHSA-vpp5-35pq-5g47, ROOT-OS-DEBIAN-11-CVE-2025-38174, ROOT-OS-DEBIAN-12-CVE-2025-38174, ROOT-OS-UBUNTU-2204-CVE-2025-38174, ROOT-OS-UBUNTU-2404-CVE-2025-38174, UBUNTU-CVE-2025-38174

## What is CVE-2025-38174?

CVE-2025-38174 is a high-severity use after free vulnerability in Debian Debian Linux, published on 4 Jul 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:

thunderbolt: Do not double dequeue a configuration request

Some of our devices crash in tb_cfg_request_dequeue():

 general protection fault, probably for non-canonical address 0xdead000000000122

 CPU: 6 PID: 91007 Comm: kworker/6:2 Tainted: G U W 6.6.65
 RIP: 0010:tb_cfg_request_dequeue+0x2d/0xa0
 Call Trace:
 <TASK>
 ? tb_cfg_request_dequeue+0x2d/0xa0
 tb_cfg_request_work+0x33/0x80
 worker_thread+0x386/0x8f0
 kthread+0xed/0x110
 ret_from_fork+0x38/0x50
 ret_from_fork_asm+0x1b/0x30

The circumstances are unclear, however, the theory is that
tb_cfg_request_work() can be scheduled twice for a request:
first time via frame.callback from ring_work() and second
time from tb_cfg_request().  Both times kworkers will execute
tb_cfg_request_dequeue(), which results in double list_del()
from the ctl->request_queue (the list poison deference hints
at it: 0xdead000000000122).

Do not dequeue requests that don't have TB_CFG_REQUEST_ACTIVE
bit set.

## Which versions are affected by CVE-2025-38174?

It affects 2 products.


Products: Debian Debian Linux, Linux kernel.

## How do I fix CVE-2025-38174?

Apply the vendor's patch.

## Is CVE-2025-38174 being exploited?

There is no known exploitation of CVE-2025-38174 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

- [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild)
- [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [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-2025-38174 and fix it if it is affected.

What it is: CVE-2025-38174 is a high-severity use after free vulnerability in Debian Debian Linux, published on 4 Jul 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-2025-38174 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-2025-38174/ (Markdown: https://insights.sbomify.com/CVE-2025-38174/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-38174
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-38174
- OSV: https://osv.dev/vulnerability/CVE-2025-38174

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-38174/
Summaries are generated and may contain mistakes; the official description above is the record.