According to InformationWeek:
Once the rootkit was running on a Linux-based Android smartphone, an attacker could call using a 'trigger number' to then gain 'full root access on the Android device' via TCP.
Even though the attack is only proof of concept, it presents some unpleasant possibilities. The researchers say:
an attacker can proceed to read all SMS messages on the device [or] incur the owner with long-distance costs, even potentially pinpoint the mobile device's exact GPS location.
Percoco and Papathanasiou plan to exploit an Android smartphone live at next month's Def Con conference.