GHSA-8FCC-W5HV-4GXV googleapis/mcp-toolbox: authentication bypass vulnerability in the generic opaque token validation path (validateOpaqueToken)

An authentication bypass vulnerability exists in the generic opaque token validation path validateOpaqueToken of googleapis/mcp-toolbox. When verifying an unparsed opaque token via an OAuth 2.0 introspection endpoint RFC 7662, the toolbox decodes the response into an introspectResp struct where t...

GHSA-WCPR-6G7X-P44R googleapis/mcp-toolbox: authentication bypass vulnerability in the generic opaque token validation path (validateOpaqueToken)

An authentication bypass vulnerability exists in the generic opaque token validation path validateOpaqueToken of googleapis/mcp-toolbox. When the toolbox validates an opaque token via an OAuth 2.0 introspection endpoint RFC 7662, it decodes the response into an introspectResp struct. However, the...

CVE-2026-11718

An authentication bypass vulnerability exists in the generic opaque token validation path validateOpaqueToken of googleapis/mcp-toolbox. When the toolbox validates an opaque token via an OAuth 2.0 introspection endpoint RFC 7662, it decodes the response into an introspectResp struct. However, the...

CVE-2026-11717

An authentication bypass vulnerability exists in the generic opaque token validation path validateOpaqueToken of googleapis/mcp-toolbox. When verifying an unparsed opaque token via an OAuth 2.0 introspection endpoint RFC 7662, the toolbox decodes the response into an introspectResp struct where t...

CVE-2026-11718

The CVE-2026-11718 entry concerns an authentication bypass in googleapis/mcp-toolbox: during opaque-token validation via an OAuth 2.0 introspection endpoint, the code decodes the response and checks issuer with the condition a.issuer != "" && iss != "". If the introspection response omits iss, is...

EUVD-2026-37880

An authentication bypass vulnerability exists in the generic opaque token validation path validateOpaqueToken of googleapis/mcp-toolbox. When the toolbox validates an opaque token via an OAuth 2.0 introspection endpoint RFC 7662, it decodes the response into an introspectResp struct. However, the...

CVE-2026-11718

An authentication bypass vulnerability exists in the generic opaque token validation path validateOpaqueToken of googleapis/mcp-toolbox. When the toolbox validates an opaque token via an OAuth 2.0 introspection endpoint RFC 7662, it decodes the response into an introspectResp struct. However, the...

CVE-2026-11718

An authentication bypass vulnerability exists in the generic opaque token validation path validateOpaqueToken of googleapis/mcp-toolbox. When the toolbox validates an opaque token via an OAuth 2.0 introspection endpoint RFC 7662, it decodes the response into an introspectResp struct. However, the...

EUVD-2026-37879

An authentication bypass vulnerability exists in the generic opaque token validation path validateOpaqueToken of googleapis/mcp-toolbox. When verifying an unparsed opaque token via an OAuth 2.0 introspection endpoint RFC 7662, the toolbox decodes the response into an introspectResp struct where t...

PT-2026-50659

Name of the Vulnerable Software and Affected Versions googleapis/mcp-toolbox affected versions not specified Description An authentication bypass exists in the generic opaque token validation path validateOpaqueToken. When verifying an unparsed opaque token via an OAuth 2.0 introspection endpoint...

PT-2026-50660

Name of the Vulnerable Software and Affected Versions googleapis/mcp-toolbox affected versions not specified Description An authentication bypass exists in the generic opaque token validation path validateOpaqueToken. When validating an opaque token via an OAuth 2.0 introspection endpoint, the...