# CVE-2020-5901: Cross-site scripting in NGINX Controller

> Reflected XSS in NGINX Controller allows attackers to compromise the system if an admin user is logged in.

- **Severity:** Critical 9.6 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 1 Jul 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-j2cc-c3x7-54xh

## What is CVE-2020-5901?

CVE-2020-5901 is a critical cross-site scripting vulnerability in NGINX Controller, published on 1 Jul 2020. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

In NGINX Controller 3.3.0-3.4.0, undisclosed API endpoints may allow for a reflected Cross Site Scripting (XSS) attack. If the victim user is logged in as admin this could result in a complete compromise of the system.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation)

## Which versions are affected by CVE-2020-5901?

It affects 1 product.


Products: F5 Nginx Controller.

## How do I fix CVE-2020-5901?

No fix has been published for CVE-2020-5901 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-5901 being exploited?

There is no known exploitation of CVE-2020-5901 in the wild and no public exploit code.

## Other vulnerabilities in NGINX Controller

- [CVE-2020-27730](https://insights.sbomify.com/CVE-2020-27730/): Path traversal in NGINX Controller (critical 9.8)
- [CVE-2020-5900](https://insights.sbomify.com/CVE-2020-5900/): Cross-site request forgery in NGINX Controller (high 8.8)
- [CVE-2020-5863](https://insights.sbomify.com/CVE-2020-5863/): Missing authorization in NGINX Controller (high 8.6)
- [CVE-2020-5894](https://insights.sbomify.com/CVE-2020-5894/): Security feature bypass in NGINX Controller (high 8.1)
- [CVE-2020-5867](https://insights.sbomify.com/CVE-2020-5867/): Supply chain in NGINX Controller (high 8.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-5901 and fix it if it is affected.

What it is: CVE-2020-5901 is a critical cross-site scripting vulnerability in NGINX Controller, published on 1 Jul 2020. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2020-5901 in the wild and no public exploit code.

Affected product: NGINX Controller. 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-2020-5901/ (Markdown: https://insights.sbomify.com/CVE-2020-5901/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-5901
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-5901
- OSV: https://osv.dev/vulnerability/CVE-2020-5901

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-5901/
Summaries are generated and may contain mistakes; the official description above is the record.