Tsup version 4.8.4 is a minor release following 4.8.3, focusing on improvements and refinements for this zero-config TypeScript bundler powered by esbuild. Both versions share a core set of functionalities aimed at simplifying the process of creating optimized bundles for libraries, CLIs, and web applications using modern JavaScript features.
The dependency list remains largely consistent between the two versions, including crucial tools like esbuild for blazing-fast builds, rollup for advanced transformations, sucrase for faster development builds, and chokidar for efficient file watching. Development dependencies, which facilitate testing and development of tsup itself, are also nearly identical, featuring libraries like jest, typescript, and various @types/* packages. typescript at version 4.2.3, remains as a peer dependency.
The most noticeable difference between versions 4.8.3 and 4.8.4 lies in the dist metadata. The fileCount decreases from 11 to 10, and unpackedSize slightly reduces from 757324 to 756939 bytes. This suggests internal optimizations or the removal of a redundant file in version 4.8.4, potentially leading to a marginally smaller installation footprint.
For developers considering Tsup, these versions are well-equipped to handle modern TypeScript bundling needs, streamlining the build process and allowing developers to focus on writing code rather than wrestling with complex configurations. The speed provided by esbuild and the zero-config approach makes Tsup an attractive choice for projects of all sizes. Potential users should always check the changelog if available for detailed information on bug fixes and more specific changes for each release.
All the vulnerabilities related to the version 4.8.4 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.