CVE-2026-11719: MCP Toolbox for Databases Authenticated Authorization Bypass Vulnerability

HIGH
Advisory Identifier: GHSA-5gf6-gc35-xjpc
CWE-862
Published
Advisory Summary

CVE-2026-11719 is a HIGH authenticated authorization bypass vulnerability (CWE-862: Missing Authorization) affecting MCP Toolbox for Databases libraries in the Go ecosystem. The issue involves authenticated authorization bypass. Remediation is available by upgrading affected packages to version 1.4.0.

CVE-2026-11719 at a Glance

CVE Identifier CVE-2026-11719
GHSA Identifier GHSA-5gf6-gc35-xjpc
Severity HIGH
CVSS v3.1 Base Score N/A
CWE Classification CWE-862: Missing Authorization
Affected Product MCP Toolbox for Databases
Package Ecosystem Go
Published Date
Last Updated

How to Fix CVE-2026-11719

To remediate this vulnerability, upgrade all affected MCP Toolbox for Databases dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

github.com/googleapis/mcp-toolbox fixed: 1.4.0
Upgrade github.com/googleapis/mcp-toolbox to 1.4.0
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

inspect dependencies for github.com/googleapis/mcp-toolbox

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-11719, inspect your project dependencies for MCP Toolbox for Databases:

inspect dependencies for github.com/googleapis/mcp-toolbox

Analyze the terminal output to locate any version of MCP Toolbox for Databases in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.4.0), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-862: Missing Authorization, where the product does not perform an authorization check when an actor attempts to access a resource or perform an action. In MCP Toolbox for Databases, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

An authenticated authorization bypass vulnerability exists in MCP Toolbox for Databases due to missing scope enforcement across older protocol handlers. While the 2025-11-25 protocol version handler correctly enforces per-tool restrictions defined by scopesRequired, older supported protocol versions (2025-06-18, 2025-03-26, and 2024-11-05) omit this check. An authenticated client with low-privilege tokens (e.g., read) can bypass the intended per-tool scope restrictions and execute high-privilege tools (e.g., admin) simply by specifying an older protocol version in the MCP-Protocol-Version header, or by omitting the header entirely (which causes the server to default to the vulnerable 2024-11-05 handler).

CVE-2026-11719 Affected MCP Toolbox for Databases Versions

1 component(s)
Fixed Versions:
1.4.0
Product / Package Ecosystem Affected Versions Fixed Version
github.com/googleapis/mcp-toolbox
Go
< 1.4.0
1.4.0

References

Frequently Asked Questions

What is CVE-2026-11719?
CVE-2026-11719 is a security vulnerability in MCP Toolbox for Databases involving authenticated authorization bypass under CWE-862: Missing Authorization.
Which MCP Toolbox for Databases versions are affected?
Affected versions include releases prior to 1.4.0 across affected packages: github.com/googleapis/mcp-toolbox.
What version fixes CVE-2026-11719?
Upgrading to 1.4.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is github.com/googleapis/mcp-toolbox affected?
Yes, github.com/googleapis/mcp-toolbox is affected in releases prior to 1.4.0. Upgrade your dependency to 1.4.0 or later.
What CWE is associated with CVE-2026-11719?
CVE-2026-11719 is classified under CWE-862: Missing Authorization (The product does not perform an authorization check when an actor attempts to access a resource or perform an action.).
How can I check Go dependencies for CVE-2026-11719?
Run the dependency tree command: 'inspect dependencies for github.com/googleapis/mcp-toolbox'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-5gf6-gc35-xjpc",
  "modified" : "2026-06-19T17:00:02Z",
  "published" : "2026-06-18T15:32:02Z",
  "aliases" : [ "CVE-2026-11719" ],
  "summary" : "MCP Toolbox for Databases: authenticated authorization bypass",
  "details" : "An authenticated authorization bypass vulnerability exists in MCP Toolbox for Databases due to missing scope enforcement across older protocol handlers.\n\nWhile the 2025-11-25 protocol version handler correctly enforces per-tool restrictions defined by scopesRequired, older supported protocol versions (2025-06-18, 2025-03-26, and 2024-11-05) omit this check. An authenticated client with low-privilege tokens (e.g., read) can bypass the intended per-tool scope restrictions and execute high-privilege tools (e.g., admin) simply by specifying an older protocol version in the MCP-Protocol-Version header, or by omitting the header entirely (which causes the server to default to the vulnerable 2024-11-05 handler).",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/googleapis/mcp-toolbox"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.4.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-11719"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/googleapis/mcp-toolbox/pull/3049"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/googleapis/mcp-toolbox/pull/3335"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/googleapis/mcp-toolbox"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-862" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-06-19T17:00:02Z",
    "nvd_published_at" : "2026-06-18T14:17:20Z"
  }
}