CVE-2026-64849: MLflow Server-Side Request Forgery Vulnerability

Patch now

CRITICAL 9.3EXPLOITEDREMOTEUPGRADE

CVE-2026-64849 is a critical-severity flaw (CVSS 9.3) affecting mlflow, reported as exploited in the wild. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

MLflow is an open source AI engineering platform for agents, large language models, and machine learning models. Starting in 3.3.0 and prior to 3.15.0, the unauthenticated POST /api/2.0/mlflow/webhooks/{id}/test endpoint calls _validate_webhook_url() in mlflow/utils/validation.py only for the original URL while mlflow/webhooks/delivery.py follows redirects and re-resolves the hostname without pinning the validated address, allowing attackers to r

Why this priority

Critical severity
EPSS top 4%: very likely to be exploited
Exploited in the wild (CISA KEV)
Public exploit reference
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	9.3 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	10.0% (top 4%)
CISA exploited list	Yes, fix due 2026-09-02
Weakness	CWE-918
Published	2026-08-17
Last modified	2026-10-26

Publisher (CNA): GitHub, Inc. · Vendor: lfprojects

Last updated 2026-10-26 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-08-17 22:17 UTCPublished CVE record published
2026-08-19Exploited Added to the CISA Known Exploited Vulnerabilities list
2026-09-02Deadline CISA due date for US federal agencies to patch
2026-10-26 13:10 UTCUpdated Record last modified

lfprojects mlflow UPGRADE

Affected: >= 3.3.0 and < 3.15.0

Fixed in: 3.15.0

Safe to downgrade to: a release before 3.3.0

1. Check installed version

apt-cache policy mlflow || rpm -q mlflow || mlflow --version

2. UPGRADE to 3.15.0 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade mlflow

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade mlflow

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 3.3.0 (Debian / Ubuntu)

apt-cache madison mlflow sudo apt install mlflow=<VERSION_BEFORE_3.3.0> sudo apt-mark hold mlflow

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list mlflow sudo dnf downgrade mlflow-<VERSION_BEFORE_3.3.0> sudo dnf versionlock add mlflow

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Exact fixes by distribution

Python (pip) · mlflow · FIXED · 3.15.0 · vulnerable: >= 3.3.0, < 3.15.0 · source

pip install --upgrade "mlflow>=3.15.0" pip show mlflow

Fedora 46 · flare-im · FIXED · 0.22.7-1.fc46 · FEDORA-2026-cd5e8062a1 · source

sudo dnf upgrade --advisory=FEDORA-2026-cd5e8062a1

Fedora ELN · libdnf · FIXED · 0.76.0-2.eln159 · FEDORA-2026-dbd263e9d4 · source

sudo dnf upgrade --advisory=FEDORA-2026-dbd263e9d4

Public exploits and detection

Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.

GitHub PoC: codeb0ssx/CVE-2026-64849-PoC (0 stars)
GitHub PoC: BiuTrap/CVE-2026-64849 (0 stars)
GitHub PoC: zavisco/CVE-2026-64849.yaml (0 stars)
Write-up: github.com/mlflow/mlflow/issues/24179
Write-up: github.com/mlflow/mlflow/security/advisories/GHSA-7gwp-5pfp-969j
Nuclei scan template: MLflow Webhook SSRF - Unauthenticated Full-Read via Redirect Bypass

Verify at the official source NVD · CVE Program · CISA KEV catalog · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-64849?

mlflow: upgrade to 3.15.0. Exact commands for each OS are on this page.

Is CVE-2026-64849 being exploited?

Yes. CVE-2026-64849 is on the CISA Known Exploited Vulnerabilities list, so treat it as patch-now.

What does CVE-2026-64849 affect?

CVE-2026-64849 affects mlflow. Severity is critical (CVSS 9.3). MLflow is an open source AI engineering platform for agents, large language models, and machine learning models. Starting in 3.3.0 and prior to 3.15.0, the unauthenticated POST /api/2.0/mlflow/webhooks/{id}/test endpoint calls _validate_web

How urgent is CVE-2026-64849?

Priority 91/100. Critical severity; EPSS top 4%: very likely to be exploited; Exploited in the wild (CISA KEV); Public exploit reference; Remotely exploitable, no login, no user action

Related CVEs

CVE-2026-8147 HIGH 8.1 UPGRADE In MLflow versions prior to 3.14.0, when running with authentication enabled, the trace API endpoints lack pro

References

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