# CVE-2026-64337: usb: mtu3: unmap request DMA on queue failure

> A missing DMA unmap in the Linux kernel mtu3 USB driver can lead to resource leaks and potential denial of service.

- **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:** 25 Jul 2026
- **Updated:** 17 Aug 2026
- **Also known as:** BELL-CVE-2026-64337, DEBIAN-CVE-2026-64337, GHSA-wvfq-6rwv-77cq, ROOT-OS-UBUNTU-2204-CVE-2026-64337, UBUNTU-CVE-2026-64337

## What is CVE-2026-64337?

CVE-2026-64337 is a medium-severity memory corruption vulnerability in Linux kernel, published on 25 Jul 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:

usb: mtu3: unmap request DMA on queue failure

mtu3_gadget_queue() maps the request before checking whether
the QMU GPD ring can accept another transfer. the request is
returned with -EAGAIN before it is linked on the endpoint
request list if mtu3_prepare_transfer() fails.

Normal completion and dequeue paths unmap requests from
mtu3_req_complete(), but this error path never reaches that
helper, so the DMA mapping is left active. Unmap the request
before returning from the failed queue path.

## Which versions are affected by CVE-2026-64337?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-64337?

Apply the vendor's patch.

## Is CVE-2026-64337 being exploited?

There is no known exploitation of CVE-2026-64337 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-2026-64337 and fix it if it is affected.

What it is: CVE-2026-64337 is a medium-severity memory corruption vulnerability in Linux kernel, published on 25 Jul 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-2026-64337 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-2026-64337/ (Markdown: https://insights.sbomify.com/CVE-2026-64337/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64337
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64337
- OSV: https://osv.dev/vulnerability/CVE-2026-64337

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64337/
Summaries are generated and may contain mistakes; the official description above is the record.