CVEs / CVE-2026-64849
CVE-2026-64849: MLflow Server-Side Request Forgery Vulnerability
- Known exploited in the CISA KEV catalog since 19 Aug 2026
- critical 9.3 CVSS 3.1 (from the CNA)
- EPSS 10% chance of exploitation in the next 30 days, higher than 95% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
MLflow contains a server-side request forgery vulnerability that can allow attackers to reach internal or cloud metadata services and receive response_status and response_body.
Description
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 reach internal or cloud metadata services and receive response_status and response_body. This issue is fixed in version 3.15.0.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| mlflow mlflow | >= 3.3.0, < 3.15.0 | — |
| Product | Affected | Fixed in |
|---|---|---|
| mlflow (PyPI) | from 3.3.0, before 3.15.0 | 3.15.0 |
Package versions from GHSA-7gwp-5pfp-969j.
Exploitation
| In CISA KEV since | 19 Aug 2026 |
|---|---|
| Due date for US federal agencies | 2 Sep 2026 |
| Used in ransomware campaigns | Unknown |
| Required action | Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines. |
Severity
| CVSS 3.1 | 9.3 criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:NScored by the CNA ([email protected]) |
|---|---|
| Weakness | CWE-918 |
References
- CVE-2026-64849 on NVD
- CVE-2026-64849 in the CISA KEV catalog
- https://github.com/mlflow/mlflow/pull/24258 (cited by CISA)
- https://github.com/mlflow/mlflow/issues/24179 (cited by CISA)
- https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk (cited by CISA)
- https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk (cited by CISA)
- CVE-2026-64849 on OSV
- https://github.com/mlflow/mlflow/commit/ba949522477cbd5915aa55d29b0cfad7d5ddf939 Patch
- https://github.com/mlflow/mlflow/issues/24179 Exploit, Issue Tracking, Mitigation
- https://github.com/mlflow/mlflow/pull/24258 Issue Tracking, Patch
- https://github.com/mlflow/mlflow/releases/tag/v3.15.0 Release Notes
- https://github.com/mlflow/mlflow/security/advisories/GHSA-7gwp-5pfp-969j Exploit, Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-64849 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.