# CVE-2025-56225: Null dereference in n/a

> An attacker can cause a denial of service in applications using FluidSynth by providing a maliciously crafted MIDI file that triggers a null pointer dereference.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 9 Jan 2026
- **Updated:** 12 Jan 2026
- **Also known as:** DEBIAN-CVE-2025-56225, GHSA-qgg6-hj2r-3x43, OESA-2026-1065, OESA-2026-1066, OESA-2026-1067, OESA-2026-1068, OESA-2026-1069, OESA-2026-1070, UBUNTU-CVE-2025-56225, openSUSE-SU-2026:10038-1, openSUSE-SU-2026:11496-1, openSUSE-SU-2026:20291-1

## What is CVE-2025-56225?

CVE-2025-56225 is a high-severity vulnerability in n/a, published on 9 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

fluidsynth-2.4.6 and earlier versions is vulnerable to Null pointer dereference in fluid_synth_monopoly.c, that can be triggered when loading an invalid midi file.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2025-56225?

It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `fluidsynth` | openSUSE:Leap 16.0 | All versions | 2.3.5-160000.3.1 |
| `fluidsynth` | openSUSE:Tumbleweed | All versions | 2.5.2-2.1 |
| `musescore` | openSUSE:Tumbleweed | All versions | 4.7.4-1.1 |

Products: Fluidsynth Fluidsynth.

## How do I fix CVE-2025-56225?

Upgrade to a fixed version.

## Is CVE-2025-56225 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-56225 exists.

## Other vulnerabilities in n/a

- [CVE-2025-68617](https://insights.sbomify.com/CVE-2025-68617/): Use after free in fluidsynth (high 7.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-56225 and fix it if it is affected.

What it is: CVE-2025-56225 is a high-severity vulnerability in n/a, published on 9 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-56225 exists.

Affected product: n/a. 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-2025-56225/ (Markdown: https://insights.sbomify.com/CVE-2025-56225/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-56225
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-56225
- OSV: https://osv.dev/vulnerability/CVE-2025-56225

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-56225/
Summaries are generated and may contain mistakes; the official description above is the record.