# CVE-2020-10519: Unsafe configuration options in GitHub Pages leading to remote code execution on GitHub Enterprise Server

> Attacker with Pages build permissions can execute arbitrary commands on GitHub Enterprise Server via unsafe parser configuration.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 3 Mar 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-gcp3-gfr7-rcqp

## What is CVE-2020-10519?

CVE-2020-10519 is a high-severity command injection vulnerability in GitHub Enterprise Server, published on 3 Mar 2021. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A remote code execution vulnerability was identified in GitHub Enterprise Server that could be exploited when building a GitHub Pages site. User-controlled configuration of the underlying parsers used by GitHub Pages were not sufficiently restricted and made it possible to execute commands on the GitHub Enterprise Server instance. To exploit this vulnerability, an attacker would need permission to create and build a GitHub Pages site on the GitHub Enterprise Server instance. This vulnerability affected all versions of GitHub Enterprise Server prior to 2.22.7 and was fixed in 2.22.7, 2.21.15, and 2.20.24. The underlying issues contributing to this vulnerability were identified through the GitHub Security Bug Bounty program.

Weakness: CWE-77 (Improper Neutralization of Special Elements used in a Command)

## Which versions are affected by CVE-2020-10519?

It affects 1 product.


Products: Github Github.

## How do I fix CVE-2020-10519?

No fix has been published for CVE-2020-10519 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-10519 being exploited?

There is no known exploitation of CVE-2020-10519 in the wild and no public exploit code.

## Other vulnerabilities in GitHub Enterprise Server

- [CVE-2020-10516](https://insights.sbomify.com/CVE-2020-10516/): Improper access control in GitHub Enterprise Server leading to privilege escalation of organization member (critical 9.8)
- [CVE-2017-18365](https://insights.sbomify.com/CVE-2017-18365/): Deserialization in n/a (critical 9.8)
- [CVE-2020-10518](https://insights.sbomify.com/CVE-2020-10518/): Unsafe configuration options in GitHub Pages leading to remote code execution on GitHub Enterprise Server (high 8.8)
- [CVE-2021-22863](https://insights.sbomify.com/CVE-2021-22863/): Missing authorization in GitHub Enterprise Server (high 8.1)
- [CVE-2012-2055](https://insights.sbomify.com/CVE-2012-2055/): Missing authorization in n/a (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-10519 and fix it if it is affected.

What it is: CVE-2020-10519 is a high-severity command injection vulnerability in GitHub Enterprise Server, published on 3 Mar 2021. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-10519 in the wild and no public exploit code.

Affected product: GitHub Enterprise Server. 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-2020-10519/ (Markdown: https://insights.sbomify.com/CVE-2020-10519/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-10519
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-10519
- OSV: https://osv.dev/vulnerability/CVE-2020-10519

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-10519/
Summaries are generated and may contain mistakes; the official description above is the record.