# CVE-2025-66370: XML external entity in kivitendo

> Attackers can exfiltrate server files by uploading malicious ZUGFeRD invoices due to XXE vulnerability in Kivitendo.

- **Severity:** Medium 5.0 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 28 Nov 2025
- **Updated:** 15 Jan 2026
- **Also known as:** GHSA-6p6f-w7vp-pv39

## What is CVE-2025-66370?

CVE-2025-66370 is a medium-severity vulnerability in kivitendo, published on 28 Nov 2025. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Kivitendo before 3.9.2 allows XXE injection. By uploading an electronic invoice in the ZUGFeRD format, it is possible to read and exfiltrate files from the server's filesystem.

Weakness: CWE-611 (Improper Restriction of XML External Entity Reference)

## Which versions are affected by CVE-2025-66370?


## How do I fix CVE-2025-66370?

No fix has been published for CVE-2025-66370 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-66370 being exploited?

There is no known exploitation of CVE-2025-66370 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-66370 and fix it if it is affected.

What it is: CVE-2025-66370 is a medium-severity vulnerability in kivitendo, published on 28 Nov 2025. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-66370 in the wild and no public exploit code.

Affected product: kivitendo. 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-2025-66370/ (Markdown: https://insights.sbomify.com/CVE-2025-66370/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-66370
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-66370
- OSV: https://osv.dev/vulnerability/CVE-2025-66370

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-66370/
Summaries are generated and may contain mistakes; the official description above is the record.