Tsup is a zero-config TypeScript bundler powered by esbuild, designed for creating modern JavaScript libraries. Version 5.12.1 and 5.12.0 are very close, but some meaningful differences can impact developers. Both versions share the same core dependencies like esbuild, rollup, and sucrase for fast and efficient bundling. They include utilities like cac for command-line argument parsing, globby for file matching, and joycon for configuration loading. Development dependencies such as typescript, @swc/core, and testing tools such as vitest and wait-for-expect, along with plugins like @rollup/plugin-json and rollup-plugin-dts are present in both.
The key difference lies in the dist section of each package's metadata. Version 5.12.1 has an unpackedSize of 472927 bytes and was released on 2022-03-11T04:06:54.169Z, while version 5.12.0 has an unpackedSize of 472900 bytes and was released on 2022-03-07T11:59:18.460Z. This means version 5.12.1 probably addresses some internal fixes or minor adjustments that led to a slightly larger unpacked size, and released 4 days later the previous version. While not explicitly stated, the bug fixes can involve addressing edge cases, improving performance that affects developers using Tsup in complex projects or refining internal processes. Developers should upgrade to the newer version (5.12.1) to benefit from these potential improvements and ensure they are using the most stable release.
All the vulnerabilities related to the version 5.12.1 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.