Skip to content
Patch Next
Sign inAdd to your agent

← Actionable
Critical, CVSS 9.3Exploited · CISA KEVamended

MLflow: Unauthenticated full-read SSRF in webhook delivery: _validate_webhook_url bypassed via unvalidated HTTP redirects (and DNS rebinding)

CVE-2026-64849GHSA-7gwp-5pfp-969j

What to do

Vendor fix available. Upgrade each affected package to the fixed version on its release line (mlflow 3.15.0), redeploy, then verify what is actually installed.

This page has no inventory attached, so it cannot say whether you are affected. A vendor fix is not proof that your deployment is fixed.

Add to your agent

Affected packages

  • PyPI mlflow

    Affected
    >= 3.3.0, < 3.15.0
    Fixed in
    3.15.0

Sources

Severity and exploitation
Exploitation
Confirmed: listed in the CISA Known Exploited Vulnerabilities catalog.
CVSS
9.3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N
EPSS
  • CVE-2026-64849: 10.02% estimated exploitation activity in the next 30 days; percentile 95.62 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.
Source description

As published by the source; long descriptions are shortened.

Summary The default MLflow Tracking Server (mlflow server, no authentication, default SQLite backend) exposes the model-registry webhooks API unauthenticated, including a synchronous POST /api/2.0/mlflow/webhooks/{id}/test endpoint that returns the upstream response status and body to the caller. The SSRF guard added in PR #20747 (validatewebhookurl, shipped in 3.10.0) resolves the webhook hostname and rejects non-public IPs, but it is bypassable: delivery follows HTTP redirects (no allowredirects=False) and never pins the validated IP. An attacker hosts a public HTTPS endpoint that passes the guard and returns 302 Location: http://169.254.169.254/... (or http://127.0.0.1:...); MLflow follows it and never re-validates the redirect target. Because /test reflects the response body, this is an unauthenticated full-read SSRF on a default server. Details Three facts combine: 1. Webhook endpoints are unauthenticated on a default server. The only webhook authorization lives in the optional…

Dates and revisions
Published by the source
Last modified by the source
Source last checked
  1. Revision 3 · amended ·

    Amended from ghsa record GHSA-7gwp-5pfp-969j

  2. Revision 2 · amended ·

    Amended from osv record GHSA-7gwp-5pfp-969j

  3. Revision 1 · created ·

    Published from ghsa record GHSA-7gwp-5pfp-969j

Agent brief

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2026-64849

Advisory: MLflow: Unauthenticated full-read SSRF in webhook delivery: _validate_webhook_url bypassed via unvalidated HTTP redirects (and DNS rebinding)
IDs: CVE-2026-64849, GHSA-7gwp-5pfp-969j
Record: https://patchnext.com/advisories/cve-2026-64849 (revision 3, source checked 26 Oct 2026, 13:54 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Critical (CVSS 9.3)
Exploitation: confirmed: listed in the CISA Known Exploited Vulnerabilities catalog.
Vendor response: Vendor fix available; fixed versions by package: mlflow 3.15.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI mlflow: affected >= 3.3.0, < 3.15.0; fixed in 3.15.0

## Suggested inspection (read-only)
- `python -m pip show mlflow`: prints the installed version. Run with the environment that serves production active.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on mlflow.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://www.cisa.gov/known-exploited-vulnerabilities-catalog (CISA added CVE-2026-64849 to the Known Exploited Vulnerabilities catalog on 2026-08-19.)
- Verified: https://github.com/advisories/GHSA-7gwp-5pfp-969j (GitHub-reviewed advisory GHSA-7gwp-5pfp-969j lists affected ranges: PyPI mlflow >=3.3.0 <3.15.0)
- Verified: https://osv.dev/vulnerability/GHSA-7gwp-5pfp-969j (OSV record GHSA-7gwp-5pfp-969j lists affected ranges: PyPI mlflow >=3.3.0 <3.15.0 (fixed))

Commands are suggestions: review each one before running it.

Loading voting…