# CVE-2023-34325: Multiple vulnerabilities in libfsimage disk handling

> A stack buffer overflow in Xen's libfsimage allows guest-controlled input to trigger memory corruption, potentially leading to code execution with root privileges.

- **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:** 5 Jan 2024
- **Updated:** 4 Nov 2025
- **Also known as:** ALPINE-CVE-2023-34325, DEBIAN-CVE-2023-34325, GHSA-gwmw-qvr5-88j2, UBUNTU-CVE-2023-34325

## What is CVE-2023-34325?

CVE-2023-34325 is a high-severity memory corruption vulnerability in Xen Xen, published on 5 Jan 2024. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

[This CNA information record relates to multiple CVEs; the
text explains which aspects/vulnerabilities correspond to which CVE.]

libfsimage contains parsing code for several filesystems, most of them based on
grub-legacy code.  libfsimage is used by pygrub to inspect guest disks.

Pygrub runs as the same user as the toolstack (root in a priviledged domain).

At least one issue has been reported to the Xen Security Team that allows an
attacker to trigger a stack buffer overflow in libfsimage.  After further
analisys the Xen Security Team is no longer confident in the suitability of
libfsimage when run against guest controlled input with super user priviledges.

In order to not affect current deployments that rely on pygrub patches are
provided in the resolution section of the advisory that allow running pygrub in
deprivileged mode.

CVE-2023-4949 refers to the original issue in the upstream grub
project ("An attacker with local access to a system (either through a
disk or external drive) can present a modified XFS partition to
grub-legacy in such a way to exploit a memory corruption in grub’s XFS
file system implementation.")  CVE-2023-34325 refers specifically to
the vulnerabilities in Xen's copy of libfsimage, which is decended
from a very old version of grub.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2023-34325?

It affects 1 product.


Products: Xen Xen.

## How do I fix CVE-2023-34325?

Apply the vendor's patch.

## Is CVE-2023-34325 being exploited?

There is no known exploitation of CVE-2023-34325 in the wild and no public exploit code.

## Other vulnerabilities in Xen Xen

- [CVE-2017-10912](https://insights.sbomify.com/CVE-2017-10912/): Privilege escalation in n/a (critical 10.0)
- [CVE-2017-10918](https://insights.sbomify.com/CVE-2017-10918/): Memory corruption in n/a (critical 10.0)
- [CVE-2017-10920](https://insights.sbomify.com/CVE-2017-10920/): Memory corruption in n/a (critical 10.0)
- [CVE-2017-10921](https://insights.sbomify.com/CVE-2017-10921/): Memory corruption in n/a (critical 10.0)
- [CVE-2025-27466](https://insights.sbomify.com/CVE-2025-27466/): Mutiple vulnerabilities in the Viridian interface (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-34325 and fix it if it is affected.

What it is: CVE-2023-34325 is a high-severity memory corruption vulnerability in Xen Xen, published on 5 Jan 2024. 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-2023-34325 in the wild and no public exploit code.

Affected product: Xen Xen. 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-2023-34325/ (Markdown: https://insights.sbomify.com/CVE-2023-34325/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-34325
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-34325
- OSV: https://osv.dev/vulnerability/CVE-2023-34325

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-34325/
Summaries are generated and may contain mistakes; the official description above is the record.