# CVE-2026-64473: vfio: Remove device debugfs before releasing devres

> A use-after-free vulnerability in the Linux kernel VFIO driver allows local attackers to execute arbitrary code or escalate privileges via stale debugfs entries.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 25 Jul 2026
- **Updated:** 17 Aug 2026
- **Also known as:** BELL-CVE-2026-64473, DEBIAN-CVE-2026-64473, GHSA-fm4h-cjxv-2ppf, ROOT-OS-UBUNTU-2204-CVE-2026-64473, UBUNTU-CVE-2026-64473

## What is CVE-2026-64473?

CVE-2026-64473 is an use after free vulnerability in Linux, published on 25 Jul 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:

vfio: Remove device debugfs before releasing devres

VFIO device debugfs files created with debugfs_create_devm_seqfile()
store a devres allocated debugfs_devm_entry as inode private data.
vfio_unregister_group_dev() currently calls vfio_device_del() before
vfio_device_debugfs_exit(), but device_del() releases devres.  This can
leave debugfs entries visible with stale inode private data while
unregister waits for userspace references to drain.

Remove the per-device debugfs tree before vfio_device_del().  The debugfs
view is diagnostic only, so losing it at the start of unregister is
preferable to preserving entries whose backing storage may already have
been released.

Complete the teardown by clearing the per-device debugfs root after
removal.  This matches the global debugfs root cleanup and prevents
future users from mistaking a removed dentry for a live debugfs tree
during the remainder of unregister.

## Which versions are affected by CVE-2026-64473?


## How do I fix CVE-2026-64473?

Apply the vendor's patch.

## Is CVE-2026-64473 being exploited?

There is no known exploitation of CVE-2026-64473 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-64473 and fix it if it is affected.

What it is: CVE-2026-64473 is an use after free vulnerability in Linux, published on 25 Jul 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-2026-64473 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-2026-64473/ (Markdown: https://insights.sbomify.com/CVE-2026-64473/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64473
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64473
- OSV: https://osv.dev/vulnerability/CVE-2026-64473

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64473/
Summaries are generated and may contain mistakes; the official description above is the record.