Tsup is a zero-config TypeScript bundler powered by esbuild, designed to simplify the process of creating libraries. Comparing version 6.6.1 with its predecessor 6.6.0, developers will find a few subtle differences reflecting ongoing maintenance and improvements. Both versions share the same core dependencies like esbuild, rollup, and sucrase, ensuring a consistent experience for bundling TypeScript. The development dependencies, including testing frameworks like vitest and code quality tools like prettier, remain largely the same indicating a continued focus on code quality.
The crucial difference lies in the details. The releaseDate reveals that version 6.6.1 was released on February 12, 2023, a few days after 6.6.0 which was released on February 7, 2023. The 'unpackedSize' is also slightly different. This increment suggests bug fixes, performance tweaks, or minor adjustments that may not warrant a significant version bump but contribute to a more stable and refined user experience. For developers, this incremental update represents a commitment to ongoing support. Checking the changelog for exact details of incremental changes is highly recommended. Both versions declare peer dependencies on postcss, @swc/core, and typescript, giving flexibility and ensuring compatibility with various project setups. Tsup simplifies library creation by abstracting away the complexities of bundler configuration empowering developers to concentrate on writing high-quality code.
All the vulnerabilities related to the version 6.6.1 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.