Tsup is a zero-config bundler for TypeScript projects, designed to make the process of creating optimized builds simple and efficient. Comparing versions 5.7.3 and 5.7.2 reveals subtle yet potentially impactful changes aimed at enhancing the developer experience.
A key difference lies in the rollup dependency. Version 5.7.3 upgrades to rollup@^2.60.0 from rollup@^2.56.1 in version 5.7.2. This upgrade could bring performance improvements, bug fixes, and new features from the Rollup ecosystem. Developers should investigate Rollup's changelog for details on what this update entails, potentially unlocking new bundling strategies or compatibility with newer JavaScript syntax.
Another notable difference is the inclusion of "tsup": "^5.7.2" in the devDependencies of version 5.7.3. This is slightly unusual, as packages generally don't list older versions of themselves as development dependencies. It might be related to internal testing or ensuring compatibility in specific build scenarios.
Beyond these specific changes, both versions share a robust set of dependencies crucial for modern TypeScript bundling: esbuild for incredibly fast builds, sucrase for efficient code transformation, and postcss-load-config for seamless integration of PostCSS configurations. Developers can leverage Tsup's zero-config approach to quickly bundle their projects, benefiting from these optimized dependencies under the hood. The consistent peer dependency on typescript@^4.2.3 ensures compatibility with a common TypeScript version. Regular updates like these demonstrate ongoing maintenance and commitment to providing developers with a reliable and up-to-date bundling solution.
All the vulnerabilities related to the version 5.7.3 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.