Tsup is a zero-config bundler powered by esbuild, designed to simplify the process of packaging TypeScript libraries and applications. Comparing versions 4.11.1 and 4.11.0, the core functionality remains largely consistent, focusing on speed and ease of use for developers. Both versions support modern JavaScript features and offer excellent tree-shaking, resulting in smaller and more efficient bundles.
The key difference lies in the release date and potentially very minor internal fixes or dependency updates reflected in the updated tarball, file count and unpacked size, suggesting a possible bug fix or improvement. Both versions share identical dependencies and devDependencies, indicating no significant feature additions or breaking changes between them, this means a seamless update.
Tsuk continues to provide first-class TypeScript support, automatic externalization of dependencies, and the ability to generate multiple output formats (ESM, CJS, IIFE) with minimal configuration. Developers benefit from rapid build times due to esbuild's efficiency and simple CLI. It continues to streamline the process of creating production-ready bundles without overwhelming users with complex setup requirements. This makes it a great choice for developers.
All the vulnerabilities related to the version 4.11.1 of the package
tsup DOM Clobbering vulnerability
A DOM Clobbering vulnerability in tsup v8.3.4 allows attackers to execute arbitrary code via a crafted script in the import.meta.url to document.currentScript in cjs_shims.js components
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.