# CVE-2023-6568: Reflected XSS via Content-Type Header in mlflow/mlflow

> Attackers can execute arbitrary JavaScript in victims' browsers by injecting malicious code into the Content-Type header of POST requests to MLflow.

- **Severity:** Medium 6.5 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N`)
- **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:** Yes
- **Published:** 7 Dec 2023
- **Updated:** 2 Aug 2024
- **Also known as:** BIT-mlflow-2023-6568, GHSA-vwhf-3v6x-wff8, PYSEC-2023-260

## What is CVE-2023-6568?

CVE-2023-6568 is a medium-severity cross-site scripting vulnerability in Lfprojects Mlflow, published on 7 Dec 2023. 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

A reflected Cross-Site Scripting (XSS) vulnerability exists in the mlflow/mlflow repository, specifically within the handling of the Content-Type header in POST requests. An attacker can inject malicious JavaScript code into the Content-Type header, which is then improperly reflected back to the user without adequate sanitization or escaping, leading to arbitrary JavaScript execution in the context of the victim's browser. The vulnerability is present in the mlflow/server/auth/__init__.py file, where the user-supplied Content-Type header is directly injected into a Python formatted string and returned to the user, facilitating the XSS attack.

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

## Which versions are affected by CVE-2023-6568?

4 open source packages ship an affected version, including mlflow. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `mlflow` | Bitnami | All versions | 2.9.1 |
| `mlflow` | PyPI | All versions | 2.9.0 |
| `mlflow` | PyPI | All versions | 2.9.0 |
| `mlflow` | PyPI | All versions | 2.9.1 |

Products: Lfprojects Mlflow.

## How do I fix CVE-2023-6568?

Upgrade mlflow to a fixed version for your release line: 2.9.1 or 2.9.0.

## Is CVE-2023-6568 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-6568 exists.

Public exploit code:

- Mlflow - Cross-Site Scripting (nuclei): http/cves/2023/CVE-2023-6568.yaml

## Other vulnerabilities in Lfprojects Mlflow

- [CVE-2026-64849](https://insights.sbomify.com/CVE-2026-64849/): MLflow Server-Side Request Forgery (critical 9.3, exploited in the wild)
- [CVE-2025-15379](https://insights.sbomify.com/CVE-2025-15379/): Command Injection in mlflow/mlflow (critical 10.0)
- [CVE-2024-0520](https://insights.sbomify.com/CVE-2024-0520/): Remote Code Execution due to Full Controlled File Write in mlflow/mlflow (critical 10.0)
- [CVE-2023-6977](https://insights.sbomify.com/CVE-2023-6977/): Path Traversal: '\..\filename' (critical 10.0)
- [CVE-2023-6709](https://insights.sbomify.com/CVE-2023-6709/): Improper Neutralization of Special Elements Used in a Template Engine in mlflow/mlflow (critical 10.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-6568 and fix it if it is affected.

What it is: CVE-2023-6568 is a medium-severity cross-site scripting vulnerability in Lfprojects Mlflow, published on 7 Dec 2023. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-6568 exists.

Affected packages and fixed versions:
- mlflow (Bitnami): affected all versions; fixed in 2.9.1
- mlflow (PyPI): affected all versions; fixed in 2.9.0
- mlflow (PyPI): affected all versions; fixed in 2.9.0
- mlflow (PyPI): affected all versions; fixed in 2.9.1

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-2023-6568/ (Markdown: https://insights.sbomify.com/CVE-2023-6568/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-6568
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-6568
- OSV: https://osv.dev/vulnerability/CVE-2023-6568

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-6568/
Summaries are generated and may contain mistakes; the official description above is the record.