MLflow server can be tricked into leaking files from its own disk
Someone who can talk to your MLflow server can register a model whose 'source' points at a folder on the server itself, then download files from that folder. This can expose secrets such as passwords stored on the server.
| Severity | HighCVSS 7.5 of 10 |
|---|---|
| Being exploited? | UnclearNo reports either way yet |
| Fix available? | YesMLflow 3.17.0 · since 27 Oct 2026 |
| How sure is this? | Official, 2 sourcesBacked by an official source |
How the attack works simplified
- 1Attacker sends requestCreates prompt model version with relative path source
- 2Server stores pathSchemeless path skips validation and is saved
- 3Artifact endpoint runsServes files from the stored location
- 4Server files readIncludes configs, secrets, auth database
- ResultAttacker reads files from the server
What happened
In MLflow 3.10.0 through 3.16.1, prompt-tagged model versions accept schemeless relative paths as artifact sources, because path validation only runs for sources with a URL scheme; the get-artifact endpoint then serves files from those paths with the server process's privileges. The prompt tag is also checked by presence rather than value.
Are you affected?
You are affected if you run MLflow 3.10.0 through 3.16.1, especially an unauthenticated tracking server (the default for mlflow server) or a basic-auth deployment where users can create registered models.
| Package / product | Affected versions | Fixed in |
|---|---|---|
| mlflow · pip | >= 3.10.0, < 3.17.0 | 3.17.0 |
What to do
- Upgrade MLflow to 3.17.0 or later (pip install -U 'mlflow>=3.17.0')
- If you cannot upgrade now, restrict network access to the MLflow server to trusted users only
- Turn on authentication and limit who can create registered models, then review the server's logs for unusual model version creation
Timeline
- 27 Oct 2026, 20:17 UTCPublicly disclosed
- 27 Oct 2026, 20:17 UTCReported by NVD · NVD
- 27 Oct 2026, 20:21 UTCPicked up by Zero Radar
- 27 Oct 2026, 21:27 UTCGitHub Advisory reported on it · GitHub Advisory
- 27 Oct 2026, 21:27 UTCFixed version published: mlflow 3.17.0 · GitHub Advisory
Sources 2 reports, oldest first
Official vendor, government CERT or advisory database
- CVE-2026-116690NVD · 27 Oct 2026, 20:17 UTC
- MLflow vulnerable to arbitrary file read on unauthenticated servers via prompt model version sourceGitHub Advisory · 27 Oct 2026, 21:26 UTC
Technical details
- ID
- CVE-2026-116690 · GHSA-m65p-9j7q-6w33
- CVSS
- 7.5 / 10
- EPSS
- 0.6% chance of exploitation within 30 days
- Disclosed
- 27 Oct 2026, 20:17 UTC
- On Zero Radar
- 27 Oct 2026, 20:21 UTC (4 min after disclosure)
- Last change
- 27 Oct 2026, 21:27 UTC
The plain-language parts and the attack diagram were written by an AI model (anthropic/claude-haiku-5.5) from the sources above. Facts like versions, exploitation and dates come from the sources themselves. How Zero Radar works