CVE-2025-14279

MLFlow versions up to and including 3.4.0 are vulnerable to DNS rebinding attacks due to a lack of Origin header validation in the MLFlow REST server. This vulnerability allows malicious websites to bypass Same-Origin Policy protections and execute unauthorized calls against REST endpoints. An attacker can query, update, and delete experiments via the affected endpoints, leading to potential data exfiltration, destruction, or manipulation. The issue is resolved in version 3.5.0.

An attacker registers a domain (e.g., mlops-toolkit-update.com) and hosts malicious JavaScript. They send a targeted phishing email to a data scientist on the victim team. The scientist visits the page while their local MLFlow tracking server runs on the default localhost:5000. The attacker's DNS server rotates the domain's A record to 127.0.0.1 after initial connection—classic DNS rebinding. The malicious JavaScript now issues `fetch()` calls to `http://mlops-toolkit-update.com:5000/api/2.0/mlflow/experiments/list`, which the browser permits because the origin appears to match. The script silently exfiltrates all experiment metadata, run parameters (including any embedded secrets), and artifact URIs, then optionally deletes experiments to destroy evidence. No authentication prompt is shown; the scientist notices nothing.