Remote code execution in YouTube Android Player API SDK

Summary

The YouTube Embedded 1.2 SDK binds to a service within the YouTube Main App. After binding, a remote context is created with the flags Context.CONTEXT_INCLUDE_CODE | Context.CONTEXT_IGNORE_SECURITY. This allows the client app to remotely load code from YouTube Main App by retrieving the Main App’s ClassLoader. A potential vulnerability in the binding logic used by the client SDK where the SDK ends up calling bindService() on a malicious app rather than YT Main App. This creates a vulnerability where the SDK can load the malicious app’s ClassLoader instead, allowing the malicious app to load arbitrary code into the calling app whenever the embedded SDK is invoked. In order to trigger this vulnerability, an attacker must masquerade the Youtube app and install it on a device, have a second app that uses the Embedded player and typically distribute both to the victim outside of the Play Store.