# CVE-2017-12623: XML External Entity Reference in Apache NiFi

> An authorized user can exploit an XML External Entity vulnerability in Apache NiFi to access sensitive files via malicious templates.

- **Severity:** Medium 6.5 (`CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/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:** Yes
- **Published:** 10 Oct 2017
- **Updated:** 16 Sep 2024
- **Also known as:** GHSA-qj7f-j6h9-g5rq

## What is CVE-2017-12623?

CVE-2017-12623 is a medium-severity vulnerability in Apache Nifi, published on 10 Oct 2017. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

An authorized user could upload a template which contained malicious code and accessed sensitive files via an XML External Entity (XXE) attack. The fix to properly handle XML External Entities was applied on the Apache NiFi 1.4.0 release. Users running a prior 1.x release should upgrade to the appropriate release.

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

## Which versions are affected by CVE-2017-12623?

2 open source packages ship an affected version, including org.apache.nifi:nifi. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `org.apache.nifi:nifi` | Maven | From 1.0.0 | 1.4.0 |
| `org.apache.nifi:nifi` | Maven | From 1.0.0 | 1.4.0 |

Products: Apache Nifi.

## How do I fix CVE-2017-12623?

Upgrade org.apache.nifi:nifi to 1.4.0 or later.

## Is CVE-2017-12623 being exploited?

There is no known exploitation of CVE-2017-12623 in the wild and no public exploit code.

## Other vulnerabilities in Apache Nifi

- [CVE-2018-1309](https://insights.sbomify.com/CVE-2018-1309/): Improper Restriction of XML External Entity Reference in Apache NiFi (critical 9.8)
- [CVE-2017-15697](https://insights.sbomify.com/CVE-2017-15697/): Apache NiFi XSS issue in context path handling (critical 9.8)
- [CVE-2017-5636](https://insights.sbomify.com/CVE-2017-5636/): Injection in Apache NiFi (critical 9.8)
- [CVE-2026-68981](https://insights.sbomify.com/CVE-2026-68981/): Apache NiFi: Uncontrolled Resource Consumption through Decompression of HTTP Requests (high 8.8)
- [CVE-2023-36542](https://insights.sbomify.com/CVE-2023-36542/): Apache NiFi: Potential Code Injection with Properties Referencing Remote Resources (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2017-12623 and fix it if it is affected.

What it is: CVE-2017-12623 is a medium-severity vulnerability in Apache Nifi, published on 10 Oct 2017. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2017-12623 in the wild and no public exploit code.

Affected packages and fixed versions:
- org.apache.nifi:nifi (Maven): affected from 1.0.0; fixed in 1.4.0
- org.apache.nifi:nifi (Maven): affected from 1.0.0; fixed in 1.4.0

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-2017-12623/ (Markdown: https://insights.sbomify.com/CVE-2017-12623/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2017-12623
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-12623
- OSV: https://osv.dev/vulnerability/CVE-2017-12623

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From sbomify Insights: https://insights.sbomify.com/CVE-2017-12623/
Summaries are generated and may contain mistakes; the official description above is the record.