Esbuild versions 0.11.10 and 0.11.11 are both iterations of the exceptionally fast JavaScript bundler and minifier known for its speed and efficiency. Both versions share the same core functionality, including being licensed under MIT, using the same repository, offering similar file counts (6), and having the same unpacked size (81512 bytes). This indicates that the jump from 0.11.10 to 0.11.11 isn't adding new features in terms of file count.
The most notable difference lies in their release dates. Version 0.11.10 was released on April 13, 2021, while version 0.11.11 followed shortly after on April 15, 2021. This implies that version 0.11.11 is likely a patch release, potentially addressing bugs or performance issues identified in the preceding version.
For developers considering esbuild for their projects, this information suggests that upgrading from 0.11.10 to 0.11.11 is advisable to benefit from any potentially critical fixes. While the core functionality and file structure remain consistent, adopting the newer version ensures a more stable and refined experience. Esbuild's primary selling point remains its speed, so staying updated is paramount.
All the vulnerabilities related to the version 0.11.11 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.