# CVE-2023-53856: of: overlay: Call of_changeset_init() early

> A NULL pointer dereference in the Linux kernel's device tree overlay code can cause a system crash when an overlay application fails.

- **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:** 9 Dec 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2023-53856, DEBIAN-CVE-2023-53856, GHSA-v9q6-qjf3-fr39, ROOT-OS-DEBIAN-11-CVE-2023-53856, UBUNTU-CVE-2023-53856

## What is CVE-2023-53856?

CVE-2023-53856 is a vulnerability in Linux, published on 9 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:

of: overlay: Call of_changeset_init() early

When of_overlay_fdt_apply() fails, the changeset may be partially
applied, and the caller is still expected to call of_overlay_remove() to
clean up this partial state.

However, of_overlay_apply() calls of_resolve_phandles() before
init_overlay_changeset().  Hence if the overlay fails to apply due to an
unresolved symbol, the overlay_changeset.cset.entries list is still
uninitialized, and cleanup will crash with a NULL-pointer dereference in
overlay_removal_is_ok().

Fix this by moving the call to of_changeset_init() from
init_overlay_changeset() to of_overlay_fdt_apply(), where all other
early initialization is done.

## Which versions are affected by CVE-2023-53856?


## How do I fix CVE-2023-53856?

Apply the vendor's patch.

## Is CVE-2023-53856 being exploited?

There is no known exploitation of CVE-2023-53856 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-53856 and fix it if it is affected.

What it is: CVE-2023-53856 is a vulnerability in Linux, published on 9 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-2023-53856 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-2023-53856/ (Markdown: https://insights.sbomify.com/CVE-2023-53856/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-53856
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-53856
- OSV: https://osv.dev/vulnerability/CVE-2023-53856

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-53856/
Summaries are generated and may contain mistakes; the official description above is the record.