Esbuild version 0.17.10 represents a minor update over the previous 0.17.9 release, primarily focusing on core dependency enhancements. Both versions maintain the same underlying description as an extremely fast JavaScript and CSS bundler and minifier, a key selling point for developers seeking efficient build processes. The license remains MIT, ensuring broad compatibility and open-source usage.
The change lies within the dependencies and optional dependencies. Both lists are extensive, covering a wide range of operating systems and architectures. Each platform-specific dependency, such as @esbuild/linux-x64, sees a version bump from 0.17.9 to 0.17.10, indicating targeted improvements or bug fixes within these platform-specific binaries.
For developers, this means the update likely incorporates stability enhancements or potentially resolves specific issues encountered on particular operating systems or architectures. The core API and functionality of Esbuild likely remain unchanged, allowing for a seamless upgrade without significant code modifications. The release date difference of roughly one day suggests a focused effort on addressing immediate concerns or improvements, making 0.17.10 the recommended version for projects leveraging Esbuild across diverse deployment environments. The minimal unpacked Size increase showcases the lightweight nature of the esbuild updates. Developers prioritizing performance and cross-platform compatibility will find these incremental improvements valuable.
All the vulnerabilities related to the version 0.17.10 of the package
esbuild enables any website to send any requests to the development server and read the response
esbuild allows any websites to send any request to the development server and read the response due to default CORS settings.
esbuild sets Access-Control-Allow-Origin: * header to all requests, including the SSE connection, which allows any websites to send any request to the development server and read the response.
https://github.com/evanw/esbuild/blob/df815ac27b84f8b34374c9182a93c94718f8a630/pkg/api/serve_other.go#L121 https://github.com/evanw/esbuild/blob/df815ac27b84f8b34374c9182a93c94718f8a630/pkg/api/serve_other.go#L363
Attack scenario:
http://malicious.example.com).fetch('http://127.0.0.1:8000/main.js') request by JS in that malicious web page. This request is normally blocked by same-origin policy, but that's not the case for the reasons above.http://127.0.0.1:8000/main.js.In this scenario, I assumed that the attacker knows the URL of the bundle output file name. But the attacker can also get that information by
/index.html: normally you have a script tag here/assets: it's common to have a assets directory when you have JS files and CSS files in a different directory and the directory listing feature tells the attacker the list of files/esbuild SSE endpoint: the SSE endpoint sends the URL path of the changed files when the file is changed (new EventSource('/esbuild').addEventListener('change', e => console.log(e.type, e.data)))The scenario above fetches the compiled content, but if the victim has the source map option enabled, the attacker can also get the non-compiled content by fetching the source map file.
npm inpm run watchfetch('http://127.0.0.1:8000/app.js').then(r => r.text()).then(content => console.log(content)) in a different website's dev tools.Users using the serve feature may get the source code stolen by malicious websites.