Tsup is a modern bundler that leverages Rollup and ESBuild for incredibly fast builds and optimized output, designed to simplify creating libraries and applications. Comparing versions 1.4.1 and 1.4.0, developers will find a subtle but important update. The dependencies remain the same, ensuring consistent core functionality related to joycon, rollup, and rollup-plugin-esbuild. Similarly, the suite of development dependencies, including testing frameworks like jest, utilities like execa and fs-extra, and tooling for TypeScript and Rollup plugins, are unchanged. This indicates that the development workflow and plugin compatibility remain stable for users upgrading.
The key difference lies in the dist object. Version 1.4.1 presents a slightly larger unpackedSize of 388971 bytes compared to 1.4.0's 388816 bytes. While both have the same fileCount of 6, the increased size in the later patch release might indicate minor bug fixes, performance tweaks, or updated documentation that were packaged within the distribution. The releaseDate also demonstrates a rapid succession, with 1.4.1 released just minutes after 1.4.0. For developers, this suggests a quick response to any issues found immediately after the initial 1.4.0 release. For users currently utilizing tsup, upgrading to 1.4.1 is advisable to ensure they are benefiting from the newest refinements, even if those refinements are not explicitly detailed. This incremental upgrade path highlights Tsup's commitment to stability and continuous improvement.
All the vulnerabilities related to the version 1.4.1 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.