# CVE-2020-25911: XML External Entity vulnerability in MODX CMS

> An XML External Entity vulnerability in MODX CMS allows attackers to disclose information or cause denial of service.

- **Severity:** Critical 9.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 31 Oct 2021
- **Updated:** 4 Aug 2024
- **Also known as:** BIT-modx-2020-25911, GHSA-vhfp-9wvj-gwvg

## What is CVE-2020-25911?

CVE-2020-25911 is a critical vulnerability in n/a, published on 31 Oct 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A XML External Entity (XXE) vulnerability was discovered in the modRestServiceRequest component in MODX CMS 2.7.3 which can lead to an information disclosure or denial of service (DOS).

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

## Which versions are affected by CVE-2020-25911?

3 open source packages ship an affected version, including modx/revolution and modx. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `modx/revolution` | Packagist | All versions | 2.8.0 |
| `modx/revolution` | Packagist | All versions | 2.8.0 |
| `modx` | Bitnami | From 2.7.3 to 2.7.3 | None |

Products: Modx Modx Revolution.

## How do I fix CVE-2020-25911?

Upgrade modx/revolution to 2.8.0 or later.

## Is CVE-2020-25911 being exploited?

There is no known exploitation of CVE-2020-25911 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2017-7321](https://insights.sbomify.com/CVE-2017-7321/): Code injection in n/a (critical 9.8)
- [CVE-2017-7324](https://insights.sbomify.com/CVE-2017-7324/): Code injection in n/a (critical 9.8)
- [CVE-2017-9069](https://insights.sbomify.com/CVE-2017-9069/): MODX Revolution allows overwriting .htaccess (high 8.8)
- [CVE-2017-7322](https://insights.sbomify.com/CVE-2017-7322/): Weak cryptography in n/a (high 8.1)
- [CVE-2017-7323](https://insights.sbomify.com/CVE-2017-7323/): Server-side request forgery in n/a (high 8.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-25911 and fix it if it is affected.

What it is: CVE-2020-25911 is a critical vulnerability in n/a, published on 31 Oct 2021. 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-2020-25911 in the wild and no public exploit code.

Affected packages and fixed versions:
- modx/revolution (Packagist): affected all versions; fixed in 2.8.0
- modx/revolution (Packagist): affected all versions; fixed in 2.8.0
- modx (Bitnami): affected from 2.7.3 up to 2.7.3; no fix listed

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-2020-25911/ (Markdown: https://insights.sbomify.com/CVE-2020-25911/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-25911
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-25911
- OSV: https://osv.dev/vulnerability/CVE-2020-25911

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-25911/
Summaries are generated and may contain mistakes; the official description above is the record.