# CVE-2025-40314: usb: cdns3: gadget: Use-after-free during failed initialization and exit of cdnsp gadget

> A use-after-free in the Linux kernel's cdns3 USB gadget driver allows local attackers to cause denial of service or execute arbitrary code.

- **Severity:** Not scored
- **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:** 8 Dec 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2025-40314, DEBIAN-CVE-2025-40314, GHSA-5pr8-9989-4xqp, ROOT-OS-DEBIAN-11-CVE-2025-40314, ROOT-OS-DEBIAN-12-CVE-2025-40314, ROOT-OS-DEBIAN-13-CVE-2025-40314, ROOT-OS-UBUNTU-2204-CVE-2025-40314, ROOT-OS-UBUNTU-2404-CVE-2025-40314, UBUNTU-CVE-2025-40314

## What is CVE-2025-40314?

CVE-2025-40314 is an use after free vulnerability in Linux, published on 8 Dec 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: cdns3: gadget: Use-after-free during failed initialization and exit of cdnsp gadget

In the __cdnsp_gadget_init() and cdnsp_gadget_exit() functions, the gadget
structure (pdev->gadget) was freed before its endpoints.
The endpoints are linked via the ep_list in the gadget structure.
Freeing the gadget first leaves dangling pointers in the endpoint list.
When the endpoints are subsequently freed, this results in a use-after-free.

Fix:
By separating the usb_del_gadget_udc() operation into distinct "del" and
"put" steps, cdnsp_gadget_free_endpoints() can be executed prior to the
final release of the gadget structure with usb_put_gadget().

A patch similar to bb9c74a5bd14("usb: dwc3: gadget: Free gadget structure
 only after freeing endpoints").

## Which versions are affected by CVE-2025-40314?


## How do I fix CVE-2025-40314?

Apply the vendor's patch.

## Is CVE-2025-40314 being exploited?

There is no known exploitation of CVE-2025-40314 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-40314 and fix it if it is affected.

What it is: CVE-2025-40314 is an use after free vulnerability in Linux, published on 8 Dec 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-2025-40314 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-2025-40314/ (Markdown: https://insights.sbomify.com/CVE-2025-40314/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-40314
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-40314
- OSV: https://osv.dev/vulnerability/CVE-2025-40314

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-40314/
Summaries are generated and may contain mistakes; the official description above is the record.