Esbuild version 0.16.11 represents a minor update over the previous stable version, 0.16.10, primarily focusing on the resolution of bugs and incremental improvements. While both versions share the same core functionality as an extremely fast JavaScript and CSS bundler and minifier, the key difference lies in the sub-dependency versions. In 0.16.11, all @esbuild/* packages are updated to version 0.16.11, whereas in 0.16.10, they were on version 0.16.10. This consistency across the platform specific binary packages is important for avoiding unexpected behavior from having mismatched versions as well as delivering any bug fixes or stability improvements.
Both versions support a wide array of platforms, including Linux, Windows, macOS, Android, and more, across various architectures like x64, ARM, and others. Developers seeking optimal build times for their projects will find both versions appealing, thanks to esbuild's renowned speed. The consistent license (MIT) and repository details ensure easy integration and contribution to the project. From a developer perspective, the transition from 0.16.10 to 0.16.11 should be seamless, involving a simple version update. The unpacked and packaged size of the library does not change between versions. Users are encouraged to update to the latest version to benefit from the newest patches and refinements.
All the vulnerabilities related to the version 0.16.11 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.