Malicious Android app could access Shared Preferences of the Nextcloud Android client

Nextcloud Android app is the Android client for Nextcloud. In versions prior to 3.16.1, a malicious app on the same device could have gotten access to the shared preferences of the Nextcloud Android application. This required user-interaction as a victim had to initiate the sharing flow and choose the malicious app. The shared preferences contain some limited private data such as push tokens and the account name. The vulnerability is patched in version 3.16.1.