webpack-dev-server users' source code may be stolen when they access a malicious web site with non-Chromium based browser

Vulnerability Description

webpack-dev-server allows users to use webpack with a development server that provides live reloading. Prior to version 5.2.1, webpack-dev-server users' source code may be stolen when you access a malicious web site with non-Chromium based browser. The `Origin` header is checked to prevent Cross-site WebSocket hijacking from happening, which was reported by CVE-2018-14732. But webpack-dev-server always allows IP address `Origin` headers. This allows websites that are served on IP addresses to connect WebSocket. An attacker can obtain source code via a method similar to that used to exploit CVE-2018-14732. Version 5.2.1 contains a patch for the issue.

References

• https://github.com/webpack/webpack-dev-server/security/advisories/GHSA-9jgg-88mc-972h
• https://github.com/webpack/webpack-dev-server/commit/5c9378bb01276357d7af208a0856ca2163db188e
• https://github.com/webpack/webpack-dev-server/commit/72efaab83381a0e1c4914adf401cbd210b7de7eb
• https://github.com/webpack/webpack-dev-server/blob/55220a800ba4e30dbde2d98785ecf4c80b32f711/lib/Server.js#L3113-L3127