# CVE-2026-90020: USB: gadget: fix NULL pointer dereference in gadget_dev_ioctl()

> A race condition in the Linux kernel USB gadget driver allows a local attacker to trigger a NULL pointer dereference, causing a system crash.

- **Severity:** Not scored
- **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:** 16 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-101394, BELL-CVE-2026-90020, DEBIAN-CVE-2026-90020, GHSA-gf8h-9qpm-2gf3, UBUNTU-CVE-2026-90020

## What is CVE-2026-90020?

CVE-2026-90020 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 gadget_dev_ioctl()

gadget_dev_ioctl() reads dev->gadget before acquiring dev->lock, but
dev->state is checked after acquiring the lock. Therefore a concurrent
bind can change the device state between these operations, which can
leave ioctl with a stale NULL gadget pointer and causing a NULL pointer
dereference at gadget->ops->ioctl.

Read dev->gadget while holding dev->lock so that the gadget pointer
and device state are sampled consistently.

## Which versions are affected by CVE-2026-90020?


## How do I fix CVE-2026-90020?

Apply the vendor's patch.

## Is CVE-2026-90020 being exploited?

There is no known exploitation of CVE-2026-90020 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-90020 and fix it if it is affected.

What it is: CVE-2026-90020 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-2026-90020 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-2026-90020/ (Markdown: https://insights.sbomify.com/CVE-2026-90020/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-90020
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-90020
- OSV: https://osv.dev/vulnerability/CVE-2026-90020

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-90020/
Summaries are generated and may contain mistakes; the official description above is the record.