Critical severity · published Jul 31, 2026
CVE-2026-14537
Authorization Bypass in MCP Toolbox Legacy HTTP Endpoints
9.8
CVSS
0.3%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 17% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MC
mcp-toolbox · Google
1.3.0; v1.4.0 · source: vendor
MT
Mcp Toolbox For Databases · Google
1.3.0; 1.4.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-14537
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-14537
Issue Tracking
https://github.com/googleapis/mcp-toolbox/pull/3435
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