{"id":"GHSA-v3f4-w7r7-v3hm","summary":"Uni-CLI: Legacy HTTP MCP transport accepted browser-originated localhost requests","details":"## Impact\n\nUni-CLI versions before 0.225.2 exposed the legacy JSON-RPC-over-HTTP MCP transport on loopback without validating browser Origin headers before routing requests. A malicious web page could send a CORS simple POST request, such as text/plain, to the local /mcp endpoint and deliver a JSON-RPC body to the dispatcher. If the user had started the local MCP HTTP transport, that page could drive tools/call requests against the user's local Uni-CLI server.\n\nThe Streamable HTTP transport already enforced this browser-to-localhost boundary. The legacy stateless HTTP path did not, so the two HTTP transports had drifted. This issue is about the browser-to-localhost boundary; it does not change Uni-CLI's local-code-execution trust model.\n\n## Patches\n\nVersion 0.225.2 fixes the issue by moving the Origin policy into a shared guard and applying it before routing in both HTTP transports. Non-loopback browser Origins are rejected with HTTP 403 before health, OAuth, or /mcp dispatch runs. Non-browser clients that omit Origin remain supported.\n\n## Workarounds\n\nUpgrade to 0.225.2 or later. If upgrading is not immediately possible, do not expose the legacy HTTP MCP transport to browser-originated traffic; use the default stdio transport or the Streamable HTTP transport instead.\n\n## Credits\n\nReported privately by Ryan Vonbrubeck ([@dodge1218](https://github.com/dodge1218)).","modified":"2026-09-10T03:50:50.682466091Z","published":"2026-06-19T21:43:09Z","database_specific":{"github_reviewed_at":"2026-06-19T21:43:09Z","nvd_published_at":null,"cwe_ids":["CWE-346","CWE-352"],"severity":"HIGH","github_reviewed":true},"references":[{"type":"WEB","url":"https://github.com/olo-dot-io/Uni-CLI/security/advisories/GHSA-v3f4-w7r7-v3hm"},{"type":"PACKAGE","url":"https://github.com/olo-dot-io/Uni-CLI"}],"affected":[{"package":{"name":"@zenalexa/unicli","ecosystem":"npm","purl":"pkg:npm/%40zenalexa/unicli"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"0.225.2"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/06/GHSA-v3f4-w7r7-v3hm/GHSA-v3f4-w7r7-v3hm.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N"}]}