Tsup version 1.4.2 introduces subtle but crucial improvements over its predecessor, version 1.4.1, enhancing the developer experience for those leveraging Rollup and ESBuild for bundling. While the core dependencies like joycon, rollup, and rollup-plugin-esbuild remain consistent, indicating stability in the foundational aspects, the key difference lies in the devDependencies.
Notably, tsup itself is updated from version 1.3.0 in 1.4.1 to version 1.4.1 in 1.4.2, suggesting internal improvements and bug fixes within the bundler. The fileCount increased from 6 to 8 and unpackedSize grew slightly, hinting at possible additions behind the scenes or more robust internal structures.
Developers should appreciate the consistent dependency versions across both releases for essential tools like typescript, prettier, and various @rollup/plugin-* packages. This consistency ensures a smooth upgrade path, minimizing potential breaking changes in the build pipeline. The update offers a refined and potentially more stable bundling process without requiring significant configuration adjustments. Users relying on tsup for efficient and modern JavaScript bundling can benefit from the incremental improvements incorporated in version 1.4.2, resulting in enhanced performance and a more reliable build workflow. Ensure to review the changelog for a complete list of fixes.
All the vulnerabilities related to the version 1.4.2 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.