CVE-2026-2652

HIGH NUCLEI

Authentication Bypass in mlflow/mlflow

Title source: cna
STIX 2.1

Exploitation Summary

CVE-2026-2652 has a Nuclei detection template available — see the Nuclei card below for the Shodan/FOFA recon queries.

Description

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.

Nuclei Templates (1)

MLflow < 3.10.0 - Authentication Bypass on FastAPI Routes
HIGHVERIFIEDby DhiyaneshDk
Shodan: http.title:"mlflow"
FOFA: app="mlflow"

References (2)

Core 2

Scores

CVSS v3 8.6
EPSS 0.0150
EPSS Percentile 71.3%
Attack Vector NETWORK
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L

CISA SSVC

Vulnrichment
Exploitation poc
Automatable yes
Technical Impact partial

Details

CWE
CWE-305
Status published
Products (3)
lfprojects/mlflow < 3.10.0
mlflow/mlflow/mlflow unspecified - 3.10.0
pypi/mlflow 0 - 3.11.0PyPI
Published May 15, 2026
Tracked Since May 15, 2026