Improper authorization in handler for custom URL scheme issue in "Mercari" App for Android prior to version 5.78.0 allows a remote attacker to lead a user to access an arbitrary website via the vulnerable App. As a result, the user may become a victim of a phishing attack.

Improper authorization in handler for custom URL scheme vulnerability in Android App 'Mercari (Merpay) - Marketplace and Mobile Payments App' (Japan version) versions prior to 4.49.1 allows a remote attacker to lead a user to access an arbitrary website and the website launches an arbitrary Activity of the app via the vulnerable App, which may result in Mercari account's access token being obtained.

Android App 'Mercari' (Japan version) prior to version 3.52.0 allows arbitrary method execution of a Java object by a remote attacker via a Man-In-The-Middle attack by using Java Reflection API of JavaScript code on WebView.