What it is
CVE-2026-2652 is an unauthenticated vulnerability affecting mlflow mlflow/mlflow. A vulnerability in mlflow/mlflow versions 3.9.0 and earlier allows unauthenticated access to certain FastAPI routes when the server is...
Vulnerability report
mlflow/mlflow Authentication Bypass
mlflow / mlflow/mlflow · affected before 3.10.0
Decision summary
Direct answers before the deeper technical record.
What it is
CVE-2026-2652 is an unauthenticated vulnerability affecting mlflow mlflow/mlflow. A vulnerability in mlflow/mlflow versions 3.9.0 and earlier allows unauthenticated access to certain FastAPI routes when the server is...
Is it exploited?
Yes. KEVIntel tracks this CVE as a known exploited vulnerability. Confidence is high.
Who is affected?
mlflow / mlflow/mlflow affected before 3.10.0.
What should we do?
Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
Overview
A vulnerability in mlflow/mlflow versions 3.9.0 and earlier allows unauthenticated access to certain FastAPI routes when the server is started with authentication enabled (`--app-name basic-auth`) and served via uvicorn (ASGI). The FastAPI permission middleware only enforces authentication on `/gateway/` routes, leaving other routes such as the Job API (`/ajax-api/3.0/jobs/*`) and the OpenTelemetry trace ingestion API (`/v1/traces`) unprotected. This allows unauthenticated remote attackers to submit jobs, read job results, cancel running jobs, and inject arbitrary trace data into experiments.
The issue arises from an architectural mismatch between Flask and FastAPI authentication mechanisms, where the `_find_fastapi_validator()` function fails to handle non-`/gateway/` paths, resulting in a complete authentication bypass. This vulnerability is fixed in version 3.10.0.
Exploitation evidence
Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.
The Shadowserver
Independent exploitation attestation added to the KEVIntel record.
Nuclei Templates
Public scanner or PoC coverage increases practical exploitability.
Per-source evidence links for KEV attestations are available through the KEVIntel Pro API.
Learn about Pro API access| Source | Added |
|---|---|
| The Shadowserver First | 2026-08-07 00:00 UTC |
Detection
Make the evidence actionable in scanner, SOC, and edge-control workflows.
Raw values available in Pro and Enterprise.
Nuclei template detected 05 Jun 2026.
View Nuclei template (opens in new tab)No KEVIntel virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.
Learn about virtual patches →Scanner and exploit-framework references linked to this CVE.
| Scanner | Reference | Detected |
|---|---|---|
| Nuclei | https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-2652.yaml | 05 Jun 2026 |
Risk and context
CVSS v3.0
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L
EPSS
18.9%
These PoCs are unverified and could contain malware. Use at your own risk.
nuclei · Created Unknown
Timeline
High-confidence, third-party attested exploitation
Public proof-of-concept code published
Scanner coverage available
Vulnerability disclosed publicly
Identifier reserved by the CNA
Pro API
Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.
GET /api/v2/pro/kevs/CVE-2026-2652
Free JSON includes basic KEV fields{
"cve_id": "CVE-2026-2652",
"confidence": "High",
"cvss_score": 8.6,
"epss_score": 0.18861,
"exploit_status": {
"exploited_in_the_wild": true,
"active_exploitation_observed": false
},
"sensor_telemetry": { "attempts": 0, "sensors": 0 }
}