Missing AuthenticationWeakness · CWE-306

CVE-2026-49257

CRITICAL · 10.0 CVSS v3.1 Published 2026-06-18
Patch available
A vendor patch is available. No clean upgrade release — apply the published patch.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
mcp-pinot is a Python-based Model Context Protocol (MCP) server for interacting with Apache Pinot. In versions 3.0.1 and below, mcp-pinot defaults to running an HTTP MCP server bound to 0.0.0.0:8080 with no authentication enabled. All MCP tools, including SQL query execution, schema creation, and table-config mutation, are reachable by any network-adjacent caller. The server proxies these calls using server-side Pinot credentials, producing a confused-deputy condition that yields full read/write access to the configured Pinot cluster. This issue has been fixed in version 3.1.0

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

mcp-pinot versions 3.0.1 and below run an unauthenticated HTTP MCP server bound to 0.0.0.0:8080, exposing all MCP tools (SQL execution, schema creation, table-config mutation) to any network-adjacent caller. The server proxies requests using its own Pinot credentials, creating a confused-deputy condition that grants attackers full read/write access to the configured Pinot cluster.

MitigationUpgrade to version 3.1.0 or later which includes authentication. If immediate upgrade is not feasible, restrict network access to the MCP server port using firewall rules or network segmentation.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify if mcp-pinot is installed or running
    Check for mcp-pinot processes or packages: look for 'mcp-pinot' in running processes, installed npm packages (npm list -g mcp-pinot), or Python packages (pip list | grep mcp-pinot). Also check for services or containers referencing pinot-mcp.
    Affected if mcp-pinot is found installed or running on the system
  2. Determine the installed version of mcp-pinot
    Run the package manager command to get the version: for npm use 'npm list -g mcp-pinot', for pip use 'pip show mcp-pinot' or check package.json. Compare the version number to the affected range (3.0.1 and below).
    Affected if The installed version is 3.0.1 or lower, or if version cannot be determined but mcp-pinot is present
  3. Verify if HTTP server is listening on port 8080
    Run 'netstat -tuln | grep 8080' or 'ss -tuln | grep 8080' to check if port 8080 is open and listening. Alternatively, use a port scanner from another host on the same network to test TCP connectivity to port 8080.
    Affected if Port 8080 is open and accepting connections, indicating the vulnerable HTTP server is active
  4. Confirm the server binds to all network interfaces
    Check the mcp-pinot configuration file or running process parameters for the bind address. If logs or config show binding to 0.0.0.0:8080, the server is exposed to network access.
    Affected if The HTTP server binds to 0.0.0.0:8080 (all interfaces) rather than localhost (127.0.0.1:8080)
  5. Check for authentication configuration
    Inspect the mcp-pinot configuration files (look for config.json, config.yaml, or similar in the mcp-pinot working directory) for authentication-related settings such as API keys, tokens, or auth-enabled flags. Also check if environment variables for authentication are set.
    Affected if No authentication mechanism is configured or enabled in the mcp-pinot setup

A user is affected if mcp-pinot version 3.0.1 or lower is installed, the HTTP server is listening on port 8080 bound to 0.0.0.0, and no authentication is configured, allowing unauthenticated network access to the Pinot cluster.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Patch available Apply the vendor patch
Vendor patch github.com →
Interim mitigation

Upgrade to version 3.1.0 or later which includes authentication. If immediate upgrade is not feasible, restrict network access to the MCP server port using firewall rules or network segmentation.

Recommended fix High confidence

3.1.0

  1. Check the currently installed version of mcp-pinot using: pip show mcp-pinot or pip list | grep mcp-pinot
  2. Upgrade to version 3.1.0 or later using: pip install --upgrade mcp-pinot
  3. Verify the upgrade was successful by checking the installed version: pip show mcp-pinot
  4. Review the release notes or changelog for version 3.1.0 to understand what authentication mechanisms are now enabled and configure accordingly
  5. If running in production, update any deployment scripts or container configurations to use version 3.1.0 or later
Caveat Review release notes for version 3.1.0 to check if any tool interfaces or parameters changed; authentication is now required so ensure client configurations are updated

Generated from the published advisory — verify against the referenced sources before acting.

Have this fixed Scoped from the published advisory
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing3.0 h
  • Review / QA2.0 h
14.0 hours of engineering $2,490
Get the patch applied

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,984.

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-49257 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data