Tsup is a zero-config TypeScript bundler powered by esbuild, designed for creating modern JavaScript libraries. Version 3.6.1 is a patch release following closely after 3.6.0, both maintaining the core promise of effortless TypeScript bundling. Examining the package.json differences reveals subtle changes reflected primarily in the dist metadata. The unpackedSize increases slightly from 687339 bytes in version 3.6.0 to 687508 bytes in 3.6.1, a minor adjustment suggesting internal tweaks or potentially updated dependencies that don't significantly alter the API or functionality visible to the end-user. Both share identical dependency and devDependency lists, ensuring a consistent toolchain for development, including crucial tools like esbuild, Rollup, and TypeScript.
For developers, this means upgrading from 3.6.0 to 3.6.1 should be seamless and require minimal to no code adjustments. The upgrade likely addresses minor bug fixes or performance improvements within tsup itself, making it a recommended update for those already using the tool. Key features remain consistent: fast builds powered by esbuild, compatibility with various module formats, declaration file generation using rollup-plugin-dts, and straightforward configuration. Since releaseDate of v3.6.1 is very close to when v3.6.0 was released, it is recommended to use the latest version to leverage the latest bug fixes.
All the vulnerabilities related to the version 3.6.1 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.