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Fencer Intel
high 7.7

CVE-2026-4035 json

Environment Variable Resolution Vulnerability in mlflow/mlflow

published 5mo ago modified last mo. also BIT-mlflow-2026-4035 , EUVD-2026-34068 , GHSA-g35p-px32-whv6 , PYSEC-2026-2222

cvss
7.7
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.5%
EPSS 0.5% chance of exploitation in 30 days, percentile 44%
public exploits
0
none known

Summary

A vulnerability in mlflow/mlflow versions prior to 3.11.0 allows for the resolution of environment variables in AI Gateway secrets, which can be exploited to exfiltrate sensitive server-side environment credentials to an attacker-controlled endpoint. This issue arises because the `api_key` field in gateway secrets can accept `$ENV_VAR` references, which are resolved against the MLflow server's environment during runtime. The resolved secrets are then sent in provider authentication headers to the configured upstream `api_base`. This vulnerability can be exploited by low-privileged authenticated users in basic-auth deployments or by unauthenticated users in default deployments without `basic-auth`. The impact includes potential leakage of sensitive credentials such as cloud artifact credentials (`AWS_ACCESS_KEY_ID`, `AWS_SECRET_ACCESS_KEY`), which could lead to artifact poisoning and cross-boundary code execution in downstream environments. The issue is fixed in version 3.11.0.

Patch / fix

  • pypi mlflow 3.11.0
  • bitnami mlflow 3.11.0
  • mlflow mlflow/mlflow 3.11.0

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-4035 updated cvss 7.7

python-mlflow: MLflow: Sensitive credential exfiltration via environment variable resolution in AI Gateway secrets

  • Red Hat OpenShift AI (RHOAI) rhoai/odh-mlflow-rhel9, rhoai/odh-th06-cpu-torch210-py312-rhel9, rhoai/odh-th06-rocm64-torch291-py312-rhel9, rhoai/odh-th06-cuda130-torch210-py312-rhel9, rhoai/odh-training-cuda128-torch29-py312-rhel9, rhoai/odh-pipeline-runtime-pytorch-cuda-py312-rhel9, +13 more
    not affected: inline mitigations already exist

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
5mo ago

Exploit prediction

0.52% chance of exploitation in the next 30 days, higher than 44% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • huntr.com https://huntr.com/bounties/f8e591a0-0f19-4910-b82e-16c9956f2233 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.0 9.1 CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L
CISA ADP 3.1 7.7 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
GitHub 3.0 9.1 CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L
NVD 3.1 7.7 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
CNA 3.1 7.7 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
OSV 3.0 9.1 CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L
OSV 3.1 7.7 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

Affected packages

ecosystem package affected fixed in
pypi mlflow
<3.11.0
3.11.0
bitnami mlflow
<3.11.0
3.11.0

Affected products

  • mlflow mlflow/mlflow
  • Red Hat Red Hat OpenShift AI (RHOAI)

Classification

Weakness
  • CWE-201 Insertion of Sensitive Information Into Sent Data

References

Sources

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