# CVE-2021-47267: usb: fix various gadget panics on 10gbps cabling

> A null pointer dereference in the Linux kernel USB gadget driver causes a system crash when connecting to 10Gbps USB ports without a specific descriptor.

- **Severity:** Medium 6.3 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 21 May 2024
- **Updated:** 11 May 2026
- **Also known as:** DEBIAN-CVE-2021-47267, GHSA-wf38-7v3f-5mjp, UBUNTU-CVE-2021-47267

## What is CVE-2021-47267?

CVE-2021-47267 is a medium-severity vulnerability in Linux kernel, published on 21 May 2024. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

usb: fix various gadget panics on 10gbps cabling

usb_assign_descriptors() is called with 5 parameters,
the last 4 of which are the usb_descriptor_header for:
  full-speed (USB1.1 - 12Mbps [including USB1.0 low-speed @ 1.5Mbps),
  high-speed (USB2.0 - 480Mbps),
  super-speed (USB3.0 - 5Gbps),
  super-speed-plus (USB3.1 - 10Gbps).

The differences between full/high/super-speed descriptors are usually
substantial (due to changes in the maximum usb block size from 64 to 512
to 1024 bytes and other differences in the specs), while the difference
between 5 and 10Gbps descriptors may be as little as nothing
(in many cases the same tuning is simply good enough).

However if a gadget driver calls usb_assign_descriptors() with
a NULL descriptor for super-speed-plus and is then used on a max 10gbps
configuration, the kernel will crash with a null pointer dereference,
when a 10gbps capable device port + cable + host port combination shows up.
(This wouldn't happen if the gadget max-speed was set to 5gbps, but
it of course defaults to the maximum, and there's no real reason to
artificially limit it)

The fix is to simply use the 5gbps descriptor as the 10gbps descriptor,
if a 10gbps descriptor wasn't provided.

Obviously this won't fix the problem if the 5gbps descriptor is also
NULL, but such cases can't be so trivially solved (and any such gadgets
are unlikely to be used with USB3 ports any way).

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2021-47267?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2021-47267?

Apply the vendor's patch.

## Is CVE-2021-47267 being exploited?

There is no known exploitation of CVE-2021-47267 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-2021-47267 and fix it if it is affected.

What it is: CVE-2021-47267 is a medium-severity vulnerability in Linux kernel, published on 21 May 2024. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-47267 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-2021-47267/ (Markdown: https://insights.sbomify.com/CVE-2021-47267/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-47267
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-47267
- OSV: https://osv.dev/vulnerability/CVE-2021-47267

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-47267/
Summaries are generated and may contain mistakes; the official description above is the record.