Angular: Open Redirect via Protocol-Relative URLs in Server-Side Rendering (SSR)

Angular is a development platform for building mobile and desktop web applications using TypeScript/JavaScript and other languages. Prior to 20.3.33, 21.2.25, and 22.2.1, ServerPlatformLocation in Angular server-side rendering checks for protocol-relative URLs before WHATWG URL normalization. A request path containing a popping dot segment followed by multiple slashes can bypass the raw resolveUrl check and normalize to a pathname beginning with two slashes. When Angular SSR detects a mismatch with the router's final location, it can place that pathname in an HTTP Location header, causing a browser to navigate to an attacker-controlled origin. Affected applications use @angular/platform-server and @angular/ssr and either expose compatible parameter or child route shapes or pass user-controlled navigation targets through infrastructure that preserves the relevant dot segments or semicolons. Pure client-side SPAs are not affected. This issue is fixed in versions 20.3.33, 21.2.25, and 22.2.1.