# CVE-2022-50740: wifi: ath9k: hif_usb: fix memory leak of urbs in ath9k_hif_usb_dealloc_tx_urbs()

> A memory leak in the ath9k USB WiFi driver allows local attackers to cause a denial of service by exhausting kernel memory.

- **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:** 24 Dec 2025
- **Updated:** 23 May 2026
- **Also known as:** DEBIAN-CVE-2022-50740, GHSA-3fvr-fgq3-468j, UBUNTU-CVE-2022-50740

## What is CVE-2022-50740?

CVE-2022-50740 is a memory corruption vulnerability in Linux, published on 24 Dec 2025. 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:

wifi: ath9k: hif_usb: fix memory leak of urbs in ath9k_hif_usb_dealloc_tx_urbs()

Syzkaller reports a long-known leak of urbs in
ath9k_hif_usb_dealloc_tx_urbs().

The cause of the leak is that usb_get_urb() is called but usb_free_urb()
(or usb_put_urb()) is not called inside usb_kill_urb() as urb->dev or
urb->ep fields have not been initialized and usb_kill_urb() returns
immediately.

The patch removes trying to kill urbs located in hif_dev->tx.tx_buf
because hif_dev->tx.tx_buf is not supposed to contain urbs which are in
pending state (the pending urbs are stored in hif_dev->tx.tx_pending).
The tx.tx_lock is acquired so there should not be any changes in the list.

Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

## Which versions are affected by CVE-2022-50740?


## How do I fix CVE-2022-50740?

Apply the vendor's patch.

## Is CVE-2022-50740 being exploited?

There is no known exploitation of CVE-2022-50740 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-50740 and fix it if it is affected.

What it is: CVE-2022-50740 is a memory corruption vulnerability in Linux, published on 24 Dec 2025. 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-2022-50740 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-2022-50740/ (Markdown: https://insights.sbomify.com/CVE-2022-50740/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-50740
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-50740
- OSV: https://osv.dev/vulnerability/CVE-2022-50740

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-50740/
Summaries are generated and may contain mistakes; the official description above is the record.