Vulnerability report

Exploitation Attempts Observed Confirmed Confidence Not in CISA KEV

CVE-2026-4035

mlflow/mlflow

Mlflow/mlflow · All versions (default: unaffected)

Watch CVE-2026-4035 Browse KEV feed
Severity
CVSS 7.7 · High
Confidence
Confirmed
Exploit status
Exploitation Attempts Observed in the Wild
EPSS
0.5%
First observed
21 Oct 2026
Last observed
04 Nov 2026

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2026-4035 is a vulnerability affecting mlflow/mlflow.

Have exploitation attempts been observed?

Yes. Previdian sensors have observed 92,753 exploitation attempts, 3 unique attacker IPs, and 2 countries targeting CVE-2026-4035. First observed Oct 21, 2026; last observed Nov 04, 2026. Confidence is confirmed.

Who is affected?

mlflow/mlflow all versions (default: unaffected).

What should we do?

Patch immediately, validate internet-facing exposure, and monitor for matching requests.

Overview

mlflow/mlflow

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.

Red Hat Unaffected
Red Hat OpenShift AI (RHOAI) rhoai/odh-mlflow-rhel9
All versions (default: unaffected)
Red Hat Unaffected
All versions (default: unaffected)
Red Hat Unaffected
All versions (default: unaffected)
Red Hat Unaffected
All versions (default: unaffected)
Red Hat Unaffected
All versions (default: unaffected)
Red Hat Unaffected
All versions (default: unaffected)
Red Hat Unaffected
All versions (default: unaffected)
Red Hat Unaffected
Red Hat OpenShift AI (RHOAI) rhoai/odh-th06-cpu-torch210-py312-rhel9
All versions (default: unaffected)
Red Hat Unaffected
Red Hat OpenShift AI (RHOAI) rhoai/odh-th06-cuda130-torch210-py312-rhel9
All versions (default: unaffected)
Red Hat Unaffected
Red Hat OpenShift AI (RHOAI) rhoai/odh-th06-rocm64-torch291-py312-rhel9
All versions (default: unaffected)
Red Hat Unaffected
Red Hat OpenShift AI (RHOAI) rhoai/odh-training-cuda128-torch29-py312-rhel9
All versions (default: unaffected)
Red Hat Unaffected
All versions (default: unaffected)
Red Hat Unaffected
All versions (default: unaffected)
Red Hat Unaffected
All versions (default: unaffected)
Red Hat Unaffected
All versions (default: unaffected)
Red Hat Unaffected
All versions (default: unaffected)
Red Hat Unaffected
All versions (default: unaffected)
Red Hat Unaffected
All versions (default: unaffected)
Red Hat Unaffected
All versions (default: unaffected)
mlflow Affected
mlflow/mlflow
Before 3.11.0
Published
03 Jun 2026
Attempts Observed Since
21 Oct 2026
Attack vector
Remote
Complexity
Low
Privileges
Low
User interaction
None

CVE References

Exploitation evidence

Evidence of exploitation attempts

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploitation Attempts Observed in the Wild

Previdian

Recorded 03 Nov 2026

Previdian sensors observed exploitation attempts targeting this vulnerability.

Exploitation Attempts Observed

Previdian sensor

First observed 03 Nov 2026

Previdian sensors observed exploitation attempts targeting this vulnerability.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the Previdian Pro API.

Learn about Pro API access
Source Added
Previdian Sensors First 2026-11-03 09:11 UTC

Operational indicators for this CVE are listed under Detection.

Sensor telemetry

Previdian Sensor Observations

Previdian sensor observations are exploitation attempts targeting this vulnerability. They do not show that the target was vulnerable or that the attempt succeeded. The cards and chart show volume, unique attackers, and daily activity.

92,753

Attempts observed

3

Unique attacker IPs

2

Attacker countries

NL · US

4

Sensors observed

CVE-2026-4035 exploitation attempts over the last 16 days

Daily events observed by Previdian sensors

Updated 04 Nov 2026

0
960
3,384
3,812
3,288
3,800
4,596
4,452
3,812
16,648
3,684
11,968
5,936
8,088
9,528
8,797
20 Oct 24 Oct 28 Oct 4 Nov

First observed 21 Oct 2026 · Last observed 04 Nov 2026

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Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
User-Agents
Callback hosts
8
3
1

Request targets and User-Agents available in Pro. Callback host details available in Enterprise.

Scanner coverage

No scanner integrations recorded yet.

Virtual patch status

No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

Attacker IP Indicators

Attacker IP indicators observed · available in Pro and Enterprise.

Sensor-derived attacker IP indicators are available to Pro and Enterprise accounts under Detection and through the Pro API.

Learn about Pro API access

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

7.7 High

Potential damage if exploited. Separate from whether attackers are using it.

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

EPSS

0.5%

Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.

Weaknesses

Insertion of Sensitive Information Into Sent Data CWE-201

All CVSS Scores

CVSS v3.1 7.7 High

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

CVSS v3.0 9.1 Critical

CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L

Timeline

From disclosure to observed exploitation attempts

  1. 08:57 UTC

    Observed by Previdian sensors

    Previdian sensors observed exploitation attempts targeting this vulnerability.

  2. 14:39 UTC

    Indicators of compromise added (3)

    Indicators of compromise recorded

  3. 07:18 UTC

    CVE published

    Vulnerability disclosed publicly

  4. 02:17 UTC

    CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

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  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2026-4035

Sample API response 
{
  "cve_id": "CVE-2026-4035",
  "confidence": "Confirmed",
  "cvss_score": 7.7,
  "cvss_estimated": false,
  "epss_score": 0.00521,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": true
  },
  "sensor_telemetry": { "attempts": 92753, "sensors": 4 }
}