Summary Missing check vulnerability in the static file handler allows any client to access the files in the server's file system Details When "staticFiles" is set in the "serve" settings in the configuration file, the following handler doesn't check if "absolutePath" is still under the directory provided as "staticFiles"; if (staticFiles) { router.get('/:relativePath+', async request => { let { relativePath } = request.params; if (!relativePath) { relativePath = 'index.html'; } const absolutePath = path.join(baseDir, staticFiles, relativePath); if (absolutePath.includes(staticFiles) && (await pathExists(absolutePath))) { const readStream = fs.createReadStream(absolutePath); return new Response(readStream as any, { status: 200, }); } return undefined; }); Example scenario To reproduce it, set "staticFiles" to the relative path of a directory in ".meshrc.yml"; serve: staticFiles: ./public Then start the server with "mesh dev", and browse to "/..%2fpackage.json" then you will see the content of "package.json". You can even go deeper to see sensitive data; "/..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2fetc/passwd" Impact and solution If "staticFiles" is set under "serve" in the configuration file. you have two options to fix vulnerability; - Update "@graphql-mesh/cli" to a version higher than "0.82.21", and if you use "@graphql-mesh/http", update it to a version higher than "0.3.18" - Remove "staticFiles" option from the configuration, and use other solutions to serve static files. Credits Thanks "alanwillms@gmail.com" (mailto:alanwillms@gmail.com) for reporting this vulnerability with details