Security readout for executives and security teams
Plain-English summary
MLflow 3.4.0 contains hard-coded default credentials in its basic authentication configuration. A remote attacker may bypass authentication and gain administrator-level code execution if an affected installation is reachable. This is business-critical where MLflow manages models, experiments, credentials, or production AI workflows.
Executive priority
Treat this as urgent for any organization using MLflow 3.4.0. The risk is direct administrative compromise of an AI/ML platform, but current evidence does not prove active exploitation.
Technical view
The reported flaw is in MLflow's basic_auth.ini, which contains hard-coded default credentials. ZDI states authentication is not required and successful exploitation can execute arbitrary code as administrator. The source bundle identifies MLflow 3.4.0 as affected; broader version impact is not established here.
Likely exposure
Exposure is most likely for organizations running MLflow 3.4.0, especially instances reachable from internal networks, VPN users, or the internet. The provided evidence does not confirm other affected versions or downstream packages.
Exploitation context
The CVSS score is 9.8 with network, low-complexity, no-privilege exploitation characteristics. The bundle marks KEV as false, and no cited source in the bundle confirms active exploitation in the wild.
Researcher notes
Evidence is strong for the described flaw and severity, but incomplete for version range, fixed release, and exploitation telemetry. Do not assume products beyond MLflow 3.4.0 are affected without vendor confirmation.
Mitigation direction
- Identify all MLflow deployments and prioritize version 3.4.0 immediately.
- Review the vendor PR and advisories for confirmed fixed versions or configuration guidance.
- Remove or rotate any unchanged default basic authentication credentials.
- Limit MLflow access to trusted networks while remediation is validated.
- Monitor for unexpected administrator actions or code execution activity.
Validation and detection
- Confirm whether MLflow 3.4.0 is deployed in production, staging, or research environments.
- Check basic_auth.ini for hard-coded or unchanged default credentials.
- Verify MLflow administrative interfaces are not exposed to untrusted networks.
- Review MLflow and platform logs for unexpected administrator access.
- Track Red Hat, CVE, ZDI, and MLflow updates for scope changes.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-1393: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCWE-798: Credential and account abuse lookup
Authentication and credential weaknesses can make valid-account abuse and credential telemetry useful review starting points. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCredential and access behavior lookup
The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-2635 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.8 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
2 official scoresWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H3.95.9zdiCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L3.93.4redhat-SADPVulnerability scoring details
Base CVSS 3.1 score
7.3HighVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
Base CVSS 3.0 score
9.8CriticalVector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- ADP timelineredhat-SADP
Made public.
- CVE publishedCVE Program
The CVE record was published.
- ADP timelineredhat-SADP
Reported to Red Hat.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
- 2026-02-20T23:01:16.144Z: Reported to Red Hat.
- 2026-02-20T22:25:03.494Z: Made public.
Source materials
- CVE List V5 sourceCVE List V5
- ZDI-26-111CVE reference, zdi · x_research-advisory
- vendor-provided URLCVE reference, zdi · vendor-advisory
- https://access.redhat.com/security/cve/CVE-2026-2635CVE reference, redhat-SADP · vdb-entry, x_refsource_REDHAT
- RHBZ#2441514CVE reference, redhat-SADP · issue-tracking, x_refsource_REDHAT
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-2635.jsonCVE reference, redhat-SADP · x_sadp-csaf-vex
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Use of Default Password
Use of Default Password represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
Use of Hard-coded Credentials
Use of Hard-coded Credentials represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.