{"id":"EUVD-2026-32672","enisaUuid":"4b6adbd7-ffaa-3abb-af2c-f6c71c1e8366","description":"Vulnerable to DNS rebinding attacks when using SSE (http://b/499408790). During the beta phase, we implemented `allowed-origins` and `allowed-hosts` flags to align with MCP security guidelines. However, the hardcoded `Access-Control-Allow-Origin: *` header in the SSE initialization handler was inadvertently retained. This vulnerability specifically impacts users connecting via Toolbox using SSE under specification v2024-11-05.","datePublished":"May 27, 2026, 9:38:55 PM","dateUpdated":"May 28, 2026, 1:20:43 PM","baseScore":9.4,"baseScoreVersion":"4.0","baseScoreVector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H","references":"https://github.com/googleapis/mcp-toolbox/issues/3053\nhttps://github.com/googleapis/mcp-toolbox/pull/3054\n","aliases":"CVE-2026-9739\nGHSA-7pf3-8xx7-rvhf\n","assigner":"Google","epss":0.28,"enisaIdProduct":[{"id":"ef264ce7-7ed8-3bc7-ba71-39c78f3be68e","product":{"name":"MCP Toolbox for Databases","vendor":{"name":"Google"}},"product_version":"0 \u003cPR 3054 (Fix CORS bypass)"}],"enisaIdVendor":[{"id":"745bdb22-a961-3a54-99bc-6c1c0fd67f37","vendor":{"name":"Google"}}],"enisaIdVulnerability":[{"id":"7f3adc6b-5161-3fff-8510-b510bbbb36a0","vulnerability":{"id":"CVE-2026-9739","description":"Vulnerable to DNS rebinding attacks when using SSE (http://b/499408790). During the beta phase, we implemented `allowed-origins` and `allowed-hosts` flags to align with MCP security guidelines. However, the hardcoded `Access-Control-Allow-Origin: *` header in the SSE initialization handler was inadvertently retained. This vulnerability specifically impacts users connecting via Toolbox using SSE under specification v2024-11-05.","datePublished":"May 27, 2026, 9:38:55 PM","dateUpdated":"May 28, 2026, 1:20:43 PM","status":"PUBLISHED","baseScore":9.4,"baseScoreVersion":"4.0","baseScoreVector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H","references":"https://github.com/googleapis/mcp-toolbox/issues/3053\nhttps://github.com/googleapis/mcp-toolbox/pull/3054\n","enisa_id":"EUVD-2026-32672\n","assigner":"Google","epss":0.28,"dataProcessed":"Oct 30, 2026, 7:18:40 AM","vulnerabilityProduct":[{"id":"42249f53-e954-3a54-bb80-f2d9d32424d5","product":{"name":"MCP Toolbox for Databases","vendor":{"name":"Google"}},"product_version":"0 \u003cPR 3054 (Fix CORS bypass)"}],"vulnerabilityVendor":[{"id":"9ac4b8a9-a8a4-3222-a297-1b2e44602d65","vendor":{"name":"Google"}}]}},{"id":"f7e2be90-9c19-38c4-aa49-eb91497b90d0","vulnerability":{"id":"GHSA-7pf3-8xx7-rvhf","description":"MCP Toolbox for Databases vulnerable to DNS rebinding attacks","datePublished":"May 28, 2026, 12:30:29 AM","dateUpdated":"Jul 1, 2026, 8:54:22 PM","baseScore":0.0,"references":"https://nvd.nist.gov/vuln/detail/CVE-2026-9739\nhttps://github.com/googleapis/mcp-toolbox/issues/3053\nhttps://github.com/googleapis/mcp-toolbox/pull/3054\nhttps://github.com/googleapis/mcp-toolbox/commit/c4c7bd917e686de68e2be866cfe3872c3439efae\nhttps://github.com/googleapis/mcp-toolbox\n","enisa_id":"EUVD-2026-32672\n","aliases":"CVE-2026-9739\nGHSA-7pf3-8xx7-rvhf\n","epss":0.0,"dataProcessed":"Oct 25, 2026, 1:56:29 AM","vulnerabilityProduct":[],"vulnerabilityVendor":[]}}],"enisaIdAdvisory":[]}