# CVE-2026-98757: usb: cdns3: fix use-after-free in cdns3_gadget_exit()

> A use-after-free in the Linux kernel's cdns3 USB gadget driver allows local attackers to execute arbitrary code or escalate privileges.

- **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:** 18 Oct 2026
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-108936, BELL-CVE-2026-98757, DEBIAN-CVE-2026-98757, GHSA-cfx2-v35h-c74w, UBUNTU-CVE-2026-98757

## What is CVE-2026-98757?

CVE-2026-98757 is an use after free vulnerability in Linux, published on 18 Oct 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: cdns3: fix use-after-free in cdns3_gadget_exit()

cdns3_gadget_start() arms two works on system_freezable_wq:
pending_status_wq for the deferred ep0 status stage and aligned_buf_wq
for realigned request buffers. Both handlers use the cdns3_device the
works are embedded in, and cdns3_pending_setup_status_handler() also
calls the ep0 request completion.

cdns3_gadget_exit() does not wait for these works. It frees all
endpoints and aligned buffers and drops the last reference to the
gadget device, which frees priv_dev, so a work queued before the exit
can run after the free.

Fix this by waiting for both works after the gadget driver is unbound
and the IRQ is freed, when no new work can be queued, and before the
endpoints and buffers are released.

This issue was found by an in-house static analysis tool.

## Which versions are affected by CVE-2026-98757?


## How do I fix CVE-2026-98757?

Apply the vendor's patch.

## Is CVE-2026-98757 being exploited?

There is no known exploitation of CVE-2026-98757 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98757 and fix it if it is affected.

What it is: CVE-2026-98757 is an use after free vulnerability in Linux, published on 18 Oct 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-2026-98757 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-2026-98757/ (Markdown: https://insights.sbomify.com/CVE-2026-98757/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98757
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98757
- OSV: https://osv.dev/vulnerability/CVE-2026-98757

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98757/
Summaries are generated and may contain mistakes; the official description above is the record.