# CVE-2026-64585: can: esd_usb: kill anchored URBs before freeing netdevs

> A use-after-free vulnerability in the Linux kernel esd_usb CAN driver allows attackers to cause denial of service or execute code via improper URB teardown order.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **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:** 6 Aug 2026
- **Updated:** 23 Aug 2026
- **Also known as:** BELL-CVE-2026-64585, DEBIAN-CVE-2026-64585, GHSA-88mv-jf2p-hpm8, UBUNTU-CVE-2026-64585

## What is CVE-2026-64585?

CVE-2026-64585 is a high-severity use after free vulnerability in Linux, published on 6 Aug 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:

can: esd_usb: kill anchored URBs before freeing netdevs

esd_usb_disconnect() frees each CAN netdev with free_candev() inside
its per-netdev loop and only calls unlink_all_urbs(dev) afterwards.
The per-netdev private data (struct esd_usb_net_priv) is embedded in
the net_device allocation returned by alloc_candev(), so once
free_candev() has run, dev->nets[i] points to freed memory.
unlink_all_urbs() then dereferences the freed dev->nets[i] to kill the
per-netdev TX anchor (usb_kill_anchored_urbs(&priv->tx_submitted)),
clear active_tx_jobs, and reset priv->tx_contexts[].

Reorder the teardown so the anchored URBs are killed before the netdevs
are freed, matching other CAN/USB drivers in the same directory such as
ems_usb, usb_8dev and mcba_usb, which unregister, then unlink, then
free: unregister the netdevs first (which stops their TX queues), call
unlink_all_urbs(dev) once, then free the netdevs.

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

## Which versions are affected by CVE-2026-64585?


## How do I fix CVE-2026-64585?

Apply the vendor's patch.

## Is CVE-2026-64585 being exploited?

There is no known exploitation of CVE-2026-64585 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-64585 and fix it if it is affected.

What it is: CVE-2026-64585 is a high-severity use after free vulnerability in Linux, published on 6 Aug 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-2026-64585 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-2026-64585/ (Markdown: https://insights.sbomify.com/CVE-2026-64585/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64585
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64585
- OSV: https://osv.dev/vulnerability/CVE-2026-64585

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64585/
Summaries are generated and may contain mistakes; the official description above is the record.