# CVE-2020-11462: XML external entity in n/a

> Attackers can cause temporary denial of service in OpenVPN Access Server via XML Entity Expansion if the full-featured RPC2 interface is enabled.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/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:** No
- **Published:** 4 May 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-vc6m-jhq8-gmhj

## What is CVE-2020-11462?

CVE-2020-11462 is a high-severity vulnerability in n/a, published on 4 May 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An issue was discovered in OpenVPN Access Server before 2.7.0 and 2.8.x before 2.8.3. With the full featured RPC2 interface enabled, it is possible to achieve a temporary DoS state of the management interface when sending an XML Entity Expansion (XEE) payload to the XMLRPC based RPC2 interface. The duration of the DoS state depends on available memory and CPU speed. The default restricted mode of the RPC2 interface is NOT vulnerable.

Weakness: CWE-776 (Improper Restriction of Recursive Entity References in DTDs)

## Which versions are affected by CVE-2020-11462?

It affects 1 product.


Products: Openvpn Openvpn Access Server.

## How do I fix CVE-2020-11462?

No fix has been published for CVE-2020-11462 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-11462 being exploited?

There is no known exploitation of CVE-2020-11462 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2020-8953](https://insights.sbomify.com/CVE-2020-8953/): Auth bypass in n/a (critical 9.8)
- [CVE-2021-4234](https://insights.sbomify.com/CVE-2021-4234/): Denial of service in OpenVPN Access Server (high 7.5)
- [CVE-2022-33737](https://insights.sbomify.com/CVE-2022-33737/): Information disclosure in OpenVPN Access Server (high 7.5)
- [CVE-2022-33738](https://insights.sbomify.com/CVE-2022-33738/): Weak cryptography in OpenVPN Access Server (high 7.5)
- [CVE-2020-36382](https://insights.sbomify.com/CVE-2020-36382/): Denial of service in OpenVPN Access Server (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-11462 and fix it if it is affected.

What it is: CVE-2020-11462 is a high-severity vulnerability in n/a, published on 4 May 2020. 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-2020-11462 in the wild and no public exploit code.

Affected product: n/a. 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-2020-11462/ (Markdown: https://insights.sbomify.com/CVE-2020-11462/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-11462
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-11462
- OSV: https://osv.dev/vulnerability/CVE-2020-11462

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-11462/
Summaries are generated and may contain mistakes; the official description above is the record.