# CVE-2026-0545: MLflow - Authentication Bypass

> Live exploitation tracking for CVE-2026-0545 by the CrowdSec Live Exploit Tracker, built from real-world attack data crowdsourced from CrowdSec's global network.

Page: https://tracker.crowdsec.net/cves/CVE-2026-0545

## Key facts

- **Exploitation phase:** Limited Exploitation. The vulnerability is known but shows very limited attacker interest or exploitation activity.
- **CVSS score:** 9.8
- **Public exploit available:** Yes
- **Affected products:** MLflow
- **Weaknesses:** CWE-306 (Missing Authentication for Critical Function)
- **Tags:** ai_mcp

## Description

In MLflow, the FastAPI job endpoints under `/ajax-api/3.0/jobs/*` are not protected by authentication or authorization when the `basic-auth` app is enabled. This vulnerability affects the latest version of the repository. If job execution is enabled (`MLFLOW_SERVER_ENABLE_JOB_EXECUTION=true`) and any job function is allowlisted, any network client can submit, read, search, and cancel jobs without credentials, bypassing basic-auth entirely. This can lead to unauthenticated remote code execution if allowed jobs perform privileged actions such as shell execution or filesystem changes. Even if jobs are deemed safe, this still constitutes an authentication bypass, potentially resulting in job spam, denial of service (DoS), or data exposure in job results.

## CrowdSec analysis

[CVE-2026-0545](https://euvd.enisa.europa.eu/vulnerability/CVE-2026-0545) is a critical authentication bypass vulnerability in MLflow/MLflow, where FastAPI job endpoints under `/ajax-api/3.0/jobs/*` are left unprotected even when basic-auth is enabled. This flaw allows any network client to submit, read, search, and cancel jobs without credentials, potentially leading to unauthenticated remote code execution, job spam, denial of service, or data exposure. Attackers could exploit this vulnerability to execute privileged actions or disrupt ML workflows, posing a severe risk to affected deployments.

CrowdSec has been tracking this vulnerability and its exploits since 3rd of June 2026.

According to CrowdSec data, while opportunistic exploitation dominates, a portion of threat actors trying to exploit CVE-2026-0545 apply basic targeting methods such as port or service detection. This indicates emerging patterns of selective targeting.
Telemetry from the CrowdSec network also shows that exploitation activity for CVE-2026-0545 remains steady week-over-week. Attack volumes are consistent with long-term trends, indicating sustained interest from threat actors. CVE-2026-0545 continues to be an active part of the threat landscape and will likely remain this way for the forseeable future.

Attackers exploit unauthenticated access to the `/ajax-api/3.0/jobs/` endpoint, allowing them to submit and manage jobs without credentials, bypassing authentication controls.

## Timeline

- 2026-04-03: CVE Published. CVE-2026-0545 is published to NVD.
- 2026-06-03: Rule Released. CrowdSec releases a rule to detect CVE-2026-0545 exploitation attempts against the CrowdSec Network.
- 2026-06-04: CrowdSec First Seen. CrowdSec observes in-the-wild exploitation of CVE-2026-0545 for the first time.

## References

- https://huntr.com/bounties/b2e5b028-9541-4d29-8703-a76f1a3734d8
- https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-0545.yaml

## Live exploitation data

The [Live Exploit Tracker page](https://tracker.crowdsec.net/cves/CVE-2026-0545) follows observed exploitation activity for CVE-2026-0545. [Request an API key](https://tracker.crowdsec.net/request-api-key) for full access to its exploitation timeline, attacking IP addresses and blocklists.