libs/binder/Parcel.cpp in the Parcels Framework APIs 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 2016-07-01 does not validate the return value of the dup system call, which allows attackers to bypass an isolation protection mechanism via a crafted application, aka internal bug 28395952.