# CVE-2016-4047: XML external entity in n/a

> Attackers can exploit XML External Entity vulnerabilities in document parsing to track access and expose internal infrastructure information.

- **Severity:** Medium 4.3 (`CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/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:** 15 Dec 2016
- **Updated:** 6 Aug 2024
- **Also known as:** GHSA-8ffc-33px-g32x

## What is CVE-2016-4047?

CVE-2016-4047 is a medium-severity vulnerability in Open-Xchange Open-Xchange Appsuite, published on 15 Dec 2016. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

An issue was discovered in Open-Xchange OX App Suite before 7.8.1-rev8. References to external Open XML document type definitions (.dtd resources) can be placed within .docx and .xslx files. Those resources were requested when parsing certain parts of the generated document. As a result an attacker can track access to a manipulated document. Usage of a document may get tracked and information about internal infrastructure may get exposed.

Weakness: CWE-611 (Improper Restriction of XML External Entity Reference), CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)

## Which versions are affected by CVE-2016-4047?

It affects 1 product.


Products: Open-Xchange Open-Xchange Appsuite.

## How do I fix CVE-2016-4047?

No fix has been published for CVE-2016-4047 yet. Limit exposure of the affected software until one is available.

## Is CVE-2016-4047 being exploited?

There is no known exploitation of CVE-2016-4047 in the wild and no public exploit code.

## Other vulnerabilities in Open-Xchange Open-Xchange Appsuite

- [CVE-2017-13667](https://insights.sbomify.com/CVE-2017-13667/): Server-side request forgery in n/a (critical 9.9)
- [CVE-2020-12645](https://insights.sbomify.com/CVE-2020-12645/): Denial of service in n/a (critical 9.8)
- [CVE-2019-7158](https://insights.sbomify.com/CVE-2019-7158/): Missing authorization in n/a (critical 9.8)
- [CVE-2017-17060](https://insights.sbomify.com/CVE-2017-17060/): Misconfiguration in n/a (critical 9.8)
- [CVE-2017-5210](https://insights.sbomify.com/CVE-2017-5210/): Information disclosure in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2016-4047 and fix it if it is affected.

What it is: CVE-2016-4047 is a medium-severity vulnerability in Open-Xchange Open-Xchange Appsuite, published on 15 Dec 2016. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2016-4047 in the wild and no public exploit code.

Affected product: Open-Xchange Open-Xchange Appsuite. 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-2016-4047/ (Markdown: https://insights.sbomify.com/CVE-2016-4047/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2016-4047
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2016-4047
- OSV: https://osv.dev/vulnerability/CVE-2016-4047

---
From sbomify Insights: https://insights.sbomify.com/CVE-2016-4047/
Summaries are generated and may contain mistakes; the official description above is the record.