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GoogleCVE-2026-14537

Google mcp-toolbox: improper authorization

High8.1CVE-2026-14537 · Published Jul 31, 2026 · updated Aug 8, 2026

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.

Google advisory

Affected versions

PackageAffectedFixed in
mcp-toolbox
Product
<= 1.3.0No fix yet
<= v1.4.0No fix yet
Details and references
CVSS 4.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Severity from
the vendor (its own CVE record or advisory)
Weakness
CWE-863

More Google advisories

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Google mcp-toolbox: denial of service
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