# CVE-2025-15547: Jail escape by a privileged user via nullfs

> A privileged user in a FreeBSD jail with nullfs mounting enabled can escape the jail and access the host filesystem.

- **Severity:** High 8.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/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:** No
- **Published:** 9 Mar 2026
- **Updated:** 10 Mar 2026
- **Also known as:** GHSA-vpcc-r2qv-r2q4

## What is CVE-2025-15547?

CVE-2025-15547 is a high-severity vulnerability in Freebsd Freebsd, published on 9 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

By default, jailed processes cannot mount filesystems, including nullfs(4).  However, the allow.mount.nullfs option enables mounting nullfs filesystems, subject to privilege checks.

If a privileged user within a jail is able to nullfs-mount directories, a limitation of the kernel's path lookup logic allows that user to escape the jail's chroot, yielding access to the full filesystem of the host or parent jail.

In a jail configured to allow nullfs(4) mounts from within the jail, the jailed root user can escape the jail's filesystem root.

Weakness: CWE-269 (Improper Privilege Management)

## Which versions are affected by CVE-2025-15547?

It affects 1 product.


Products: Freebsd Freebsd.

## How do I fix CVE-2025-15547?

No fix has been published for CVE-2025-15547 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-15547 being exploited?

There is no known exploitation of CVE-2025-15547 in the wild and no public exploit code.

## Other vulnerabilities in Freebsd Freebsd

- [CVE-2018-17160](https://insights.sbomify.com/CVE-2018-17160/): Memory corruption in FreeBSD (critical 10.0)
- [CVE-2014-3954](https://insights.sbomify.com/CVE-2014-3954/): Memory corruption in n/a (critical 10.0)
- [CVE-2006-4304](https://insights.sbomify.com/CVE-2006-4304/): Memory corruption in n/a (critical 10.0)
- [CVE-2006-0226](https://insights.sbomify.com/CVE-2006-0226/): Integer overflow in n/a (critical 10.0)
- [CVE-2004-0002](https://insights.sbomify.com/CVE-2004-0002/): Denial of service in n/a (critical 10.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-15547 and fix it if it is affected.

What it is: CVE-2025-15547 is a high-severity vulnerability in Freebsd Freebsd, published on 9 Mar 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-2025-15547 in the wild and no public exploit code.

Affected product: Freebsd Freebsd. 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-2025-15547/ (Markdown: https://insights.sbomify.com/CVE-2025-15547/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-15547
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-15547
- OSV: https://osv.dev/vulnerability/CVE-2025-15547

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-15547/
Summaries are generated and may contain mistakes; the official description above is the record.