# CVE-2020-4020: Code injection in Companion App

> Remote attackers controlling a connected Confluence Server can execute arbitrary executables on the Atlassian Companion App due to protection mechanism failure.

- **Severity:** High 7.2 (`CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 1 Jun 2020
- **Updated:** 16 Sep 2024
- **Also known as:** GHSA-72w5-xxp4-hp3g

## What is CVE-2020-4020?

CVE-2020-4020 is a high-severity code injection vulnerability in Atlassian Companion App, published on 1 Jun 2020. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

The file downloading functionality in the Atlassian Companion App before version 1.0.0 allows remote attackers, who control a Confluence Server instance that the Companion App is connected to, execute arbitrary .exe files via a Protection Mechanism Failure.

## Which versions are affected by CVE-2020-4020?

It affects 1 product.


Products: Atlassian Companion.

## How do I fix CVE-2020-4020?

No fix has been published for CVE-2020-4020 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-4020 being exploited?

There is no known exploitation of CVE-2020-4020 in the wild and no public exploit code.

## Other vulnerabilities in Atlassian Companion App

- [CVE-2023-22524](https://insights.sbomify.com/CVE-2023-22524/): Security feature bypass in Companion for Mac (critical 9.6)
- [CVE-2020-4019](https://insights.sbomify.com/CVE-2020-4019/): Path traversal in Companion App (high 7.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-4020 and fix it if it is affected.

What it is: CVE-2020-4020 is a high-severity code injection vulnerability in Atlassian Companion App, published on 1 Jun 2020. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-4020 in the wild and no public exploit code.

Affected product: Atlassian Companion App. 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-2020-4020/ (Markdown: https://insights.sbomify.com/CVE-2020-4020/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-4020
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-4020
- OSV: https://osv.dev/vulnerability/CVE-2020-4020

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-4020/
Summaries are generated and may contain mistakes; the official description above is the record.