Authorization Bypass Through User-Controlled Key #458
Description
Incorrect hostname / protocol due to unstripped leading control characters. Leading control characters in a URL are not stripped when passed into url-parse. This can cause input URLs to be mistakenly be interpreted as a relative URL without a hostname and protocol, while the WHATWG URL parser will trim control characters and treat it as an absolute URL. If url-parse is used in security decisions involving the hostname / protocol, and the input URL is used in a client which uses the WHATWG URL parser, the decision may be incorrect. This can also lead to a cross-site scripting (XSS) vulnerability if url-parse is used to check for the javascript: protocol in URLs. See following example: const parse = require('url-parse') const express = require('express') const app = express() const port = 3000 url = parse(\"\\bjavascript:alert(1)\") console.log(url) app.get('/', (req, res) => { if (url.protocol !== \"javascript:\") {res.send(\"[CLICK ME!](file://%27/%22)\")} }) app.listen(port, () => { console.log(`Example app listening on port ${port}`) })