CVE-2026-14537 Authorization Bypass in MCP Toolbox Legacy HTTP Endpoints

What is CVE-2026-14537?

CVE-2026-14537 is a high-severity missing authorization vulnerability in Google mcp-toolbox, published on 31 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Incorrect Authorization in the direct HTTP API tool invocation endpoint in Google mcp-toolbox versions v1.3.0 and v1.4.0 allows an unauthenticated attacker to invoke tools protected by the scopeRequired feature via sending tool invocation requests through legacy HTTP endpoints when the --enable-api flag is active.

Weakness: CWE-863

Which versions are affected by CVE-2026-14537?

It affects 1 product.

Products include Google Mcp Toolbox for Databases.

How do I fix CVE-2026-14537?

No fix has been published for CVE-2026-14537 yet. Limit exposure of the affected software until one is available.

Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.

Is CVE-2026-14537 being exploited?

There is no known exploitation of CVE-2026-14537 in the wild and no public exploit code.

Other vulnerabilities in Google mcp-toolbox

• CVE-2026-11720 Path Traversal in googleapis/mcp-toolbox HTTP Tool URL Builder Critical 9.3
• CVE-2026-11717 googleapis/mcp-toolbox: authentication bypass vulnerability in the generic opaque token validation path (validateOpaqueToken) Critical 9.3
• CVE-2026-11718 googleapis/mcp-toolbox: authentication bypass vulnerability in the generic opaque token validation path (validateOpaqueToken) Critical 9.3
• CVE-2026-15829 SQL Injection and Security Boundary Bypass in googleapis/mcp-toolbox High 8.6
• CVE-2026-11719 MCP Toolbox for Databases: authenticated authorization bypass High 8.6

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-f8h2-c55w-8m5p.