Tsup, a zero-config TypeScript bundler powered by esbuild, saw a minor update from version 5.6.1 to 5.6.2 on November 12, 2021. Both versions share a core set of dependencies crucial for their functionality, including esbuild for blazing-fast builds, rollup for bundling, and sucrase for faster TypeScript/JavaScript compilation. They also rely on utilities like cac for command-line argument parsing, chalk for colorful console output, and globby for file system globbing. Key peer dependencies remain consistent, requiring TypeScript version ^4.2.3, ensuring compatibility with recent TypeScript features.
A significant change surfaces in the devDependencies. The update removes patch-package a tool for making and persisting changes to npm dependencies directly from the devDependencies in version 5.6.2. This might indicate a fix or workaround implemented within the core tsup codebase rendering the need for patching dependencies obsolete. Developers using patch-package with v5.6.1 may need to adjust their workflow if upgrading. The file count remains unchanged at 20, suggesting no addition or removal of files, and the unpacked size has a minuscule difference of 37 bytes.
Tsup aims to simplify the bundling process for TypeScript projects offering a streamlined developer experience eliminating complex configurations. The removal of patch-package as a dev dependency might signal stability improvements or internal dependency management enhancements. Developers should consider this change when upgrading, and if relying on patch-package for tsup the functionality should be verified.
All the vulnerabilities related to the version 5.6.2 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.