Tsup is a zero-config TypeScript bundler powered by esbuild, designed for creating optimized and streamlined packages. Version 6.1.2 is a minor update released shortly after 6.1.1, both maintaining the tool's core philosophy of simplifying the bundling process. Examining the package data, the primary differences between the two versions appear minimal, likely focusing on bug fixes or small internal improvements. The dependency and devDependency lists remain consistent, indicating no significant changes to core functionalities or supported tools. Both versions rely on essential libraries like esbuild for blazing-fast builds, Rollup for advanced transformations, and Sucrase for faster TypeScript and JSX transpilation.
Developers using tsup benefit from its ease of use and exceptional speed. The zero-config approach means less time spent on configuration and more time focusing on code. Support for various entry points, code splitting, and tree shaking ensures optimized bundles for different use cases, whether you're building a library, CLI tool, or web application. The consistent dependency list between versions suggests a stable and reliable toolchain, empowering developers to seamlessly integrate tsup into their workflows. The quick release of 6.1.2 following 6.1.1 points to an active maintenance cycle, providing confidence that bug fixes and small improvements are being addressed promptly. While the changes might be subtle, keeping up to date ensures access to the most refined version.
All the vulnerabilities related to the version 6.1.2 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.