server/content/SyncStorageEngine.java in SyncStorageEngine in Android 4.x before 4.4.4, 5.0.x before 5.0.2, 5.1.x before 5.1.1, and 6.x before 2016-04-01 mismanages certain authority data, which allows attackers to cause a denial of service (reboot loop) via a crafted application, aka internal bug 26513719.