Angular Use of Cache Containing Sensitive Information Vulnerability - CVE-2026-50170

Angular is a development platform for building mobile and desktop web applications using TypeScript/JavaScript and other languages. Prior to 22.0.0-rc.2 21.2.15 20.3.22 and 19.2.23 a vulnerability was discovered in angular/common when Server-Side Rendering (SSR) and hydration are enabled. The HttpTransferCache utility optimizes hydration by caching outgoing HTTP requests performed during SSR and transferring the cached state to the client-side application via TransferState. However the caching mechanism fails to inspect the withCredentials flag or the Cookie header of outgoing requests. As a result credentialed user-specific responses may be cached by default in the shared TransferState payload. When these responses are serialized into the HTML any caching layer (such as a CDN reverse proxy or shared server cache) that caches the SSR-rendered HTML page could inadvertently cache and leak one user39s private data to other users leading to a high-severity information disclosure vulnerability. This vulnerability is fixed in 22.0.0-rc.2 21.2.15 20.3.22 and 19.2.23.