# CVE-2026-43429: USB: usbtmc: Use usb_bulk_msg_killable() with user-specified timeouts

> A local attacker can hang kernel threads indefinitely by specifying long timeouts in USBTMC ioctl calls, causing a 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:** 8 May 2026
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2026-43429, DEBIAN-CVE-2026-43429, GHSA-f7gv-jp52-6999, ROOT-OS-DEBIAN-11-CVE-2026-43429, ROOT-OS-UBUNTU-2204-CVE-2026-43429, ROOT-OS-UBUNTU-2404-CVE-2026-43429, UBUNTU-CVE-2026-43429

## What is CVE-2026-43429?

CVE-2026-43429 is a medium-severity denial of service vulnerability in Linux kernel, published on 8 May 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: usbtmc: Use usb_bulk_msg_killable() with user-specified timeouts

The usbtmc driver accepts timeout values specified by the user in an
ioctl command, and uses these timeouts for some usb_bulk_msg() calls.
Since the user can specify arbitrarily long timeouts and
usb_bulk_msg() uses unkillable waits, call usb_bulk_msg_killable()
instead to avoid the possibility of the user hanging a kernel thread
indefinitely.

## Which versions are affected by CVE-2026-43429?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-43429?

Apply the vendor's patch.

## Is CVE-2026-43429 being exploited?

There is no known exploitation of CVE-2026-43429 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-2026-43429 and fix it if it is affected.

What it is: CVE-2026-43429 is a medium-severity denial of service vulnerability in Linux kernel, published on 8 May 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-2026-43429 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-2026-43429/ (Markdown: https://insights.sbomify.com/CVE-2026-43429/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-43429
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-43429
- OSV: https://osv.dev/vulnerability/CVE-2026-43429

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-43429/
Summaries are generated and may contain mistakes; the official description above is the record.