# CVE-2021-41042: XML External Entity Reference in Eclipse Lyo

> An attacker can trigger external DTD retrieval in Eclipse Lyo, potentially leading to data disclosure or denial of service.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 7 Jul 2022
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-6296-mvgp-27hp

## What is CVE-2021-41042?

CVE-2021-41042 is a medium-severity vulnerability in The Eclipse Foundation Eclipse Lyo, published on 7 Jul 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In Eclipse Lyo versions 1.0.0 to 4.1.0, a TransformerFactory is initialized with the defaults that do not restrict DTD loading when working with RDF/XML. This allows an attacker to cause an external DTD to be retrieved.

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

## Which versions are affected by CVE-2021-41042?

2 open source packages ship an affected version, including org.eclipse.lyo:lyo-parent. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `org.eclipse.lyo:lyo-parent` | Maven | From 1.0.0 | 5.0.0.Final |
| `org.eclipse.lyo:lyo-parent` | Maven | From 1.0.0 | 5.0.0.Final |

Products: Eclipse Lyo.

## How do I fix CVE-2021-41042?

Upgrade org.eclipse.lyo:lyo-parent to 5.0.0.Final or later.

## Is CVE-2021-41042 being exploited?

There is no known exploitation of CVE-2021-41042 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-41042 and fix it if it is affected.

What it is: CVE-2021-41042 is a medium-severity vulnerability in The Eclipse Foundation Eclipse Lyo, published on 7 Jul 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-41042 in the wild and no public exploit code.

Affected packages and fixed versions:
- org.eclipse.lyo:lyo-parent (Maven): affected from 1.0.0; fixed in 5.0.0.Final
- org.eclipse.lyo:lyo-parent (Maven): affected from 1.0.0; fixed in 5.0.0.Final

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-2021-41042/ (Markdown: https://insights.sbomify.com/CVE-2021-41042/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-41042
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-41042
- OSV: https://osv.dev/vulnerability/CVE-2021-41042

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-41042/
Summaries are generated and may contain mistakes; the official description above is the record.