# CVE-2026-2611: MLflow MLflow Assistant improper origin validation in /ajax-api

Source: https://junglewise.ai/threats/cve-2026-2611-mlflow-mlflow-assistant-improper-origin-validation-in-ajax-api  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-19. Updated: 2026-06-04  
License: CC BY 4.0 with a link back

CVE-2026-2611 · Severity: critical · CVSS 9.6 · Published 2026-05-19

MLflow is an open-source platform for managing the machine learning lifecycle. A security flaw in the MLflow Assistant feature allows a malicious website to send unauthorized commands to the MLflow application running on a user's local computer. If exploited, an attacker could gain full control over the victim's local machine and execute arbitrary commands, potentially leading to data theft or complete system compromise.

Technologies: [mlflow (PyPI)](https://junglewise.ai/threats/technologies/mlflow). Vendors: [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is CVE-2026-2611 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-2611 being exploited in the wild.

**How severe is CVE-2026-2611?** Critical severity, with a CVSS score of 9.6, published 19 May 2026.

**Which products and versions are affected?** mlflow (PyPI) = 3.9.0, ECOSYSTEM:introduced=3.9.0,fixed=3.10.0.

**Is there a fix for CVE-2026-2611?** Yes. mlflow (PyPI): upgrade to 3.10.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-2611 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-2611?** Check whether you run mlflow (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- mlflow (PyPI): upgrade to 3.10.0 or later

  ```sh
  pip install "mlflow>=3.10.0"
  ```


## Technical details

An improper origin validation vulnerability (CWE-346) exists in the /ajax-api endpoints of the MLflow Assistant feature in version 3.9.0. The application fails to properly restrict cross-origin requests, allowing a malicious webpage to bypass loopback-only restrictions. By sending crafted requests through a victim's browser, a remote attacker can modify the Assistant's configuration to enable full access. This configuration change allows the attacker to leverage the integrated Claude Code sub-agent to execute arbitrary shell commands on the host system. The vulnerability is exploited via a network attack vector but requires user interaction (visiting a malicious site). The issue is resolved in version 3.10.0 by implementing stricter CORS blocking for AJAX paths.

## Affected products

- MLflow mlflow 3.9.0

## Identifiers

- CVE-2026-2611
- GHSA-67c5-x5mf-rppq
- PYSEC-2026-418

## Timeline

- 2026-02-16: patched: Fix committed to repository
- 2026-05-19: disclosed: CVE-2026-2611 published
- 2026-05-19: advisory: GitHub Advisory GHSA-67c5-x5mf-rppq published

## References

- [https://github.com/mlflow/mlflow/commit/8f9c8a53af90842944101eb8b7d60706822c81bc](https://github.com/mlflow/mlflow/commit/8f9c8a53af90842944101eb8b7d60706822c81bc)
- [https://huntr.com/bounties/8462addd-b464-4a84-b6a2-5529604e6e5a](https://huntr.com/bounties/8462addd-b464-4a84-b6a2-5529604e6e5a)

## Related threats

- [MLflow arbitrary code execution in third-party scorer deserialization](https://junglewise.ai/threats/cve-2026-116692-mlflow-is-an-open-source-ai-engineering-platform-for-agents)
- [MLflow credential leak in CrewAI autolog](https://junglewise.ai/threats/cve-2026-116691-mlflow-is-an-open-source-ai-engineering-platform-for-agents)
- [MLflow path traversal in prompt model version artifact access](https://junglewise.ai/threats/cve-2026-116690-mlflow-is-an-open-source-ai-engineering-platform-for-agents)
- [MLflow unsafe deserialization in scorer endpoints](https://junglewise.ai/threats/cve-2026-115886-mlflow-is-an-open-source-ai-engineering-platform-for-agents)
- [MLflow FileStore path traversal in trace storage](https://junglewise.ai/threats/cve-2026-53995-mlflow-3-17-1-and-earlier-contains-a-path-traversal-vulnerability)