# CVE-2026-90019: usb: gadget: fix null pointer dereference in usb_put_function_instance()

> A null pointer dereference in the Linux kernel USB gadget driver allows local attackers to cause a system crash via the UVC function instance error path.

- **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:** 16 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-101324, BELL-CVE-2026-90019, DEBIAN-CVE-2026-90019, GHSA-gprv-q9q2-hpx6, UBUNTU-CVE-2026-90019

## What is CVE-2026-90019?

CVE-2026-90019 is a vulnerability in Linux, published on 16 Sep 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: gadget: fix null pointer dereference in usb_put_function_instance()

usb_put_function_instance() attempts to dereference fd inside fi struct
to get mod in uvc_alloc_inst() error path. However, fd is not allocated
until later in try_get_usb_function_instance() after allocating fi in
uvc_alloc_inst() and thus guranteed to be null in error path. Fix this
by adding a null check for fi->fd that returns if fd is null.

## Which versions are affected by CVE-2026-90019?


## How do I fix CVE-2026-90019?

Apply the vendor's patch.

## Is CVE-2026-90019 being exploited?

There is no known exploitation of CVE-2026-90019 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-90019 and fix it if it is affected.

What it is: CVE-2026-90019 is a vulnerability in Linux, published on 16 Sep 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-2026-90019 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-2026-90019/ (Markdown: https://insights.sbomify.com/CVE-2026-90019/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-90019
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-90019
- OSV: https://osv.dev/vulnerability/CVE-2026-90019

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-90019/
Summaries are generated and may contain mistakes; the official description above is the record.