Following recent security issues discovered in Android, Google made a number of changes to tighten security across its fragmented landscape. However, Google is not alone in the struggle to keep Android safe. Qualcomm, a supplier of 80% of the chipsets in the Android ecosystem, has almost as much effect on Android’s security as Google.
With this in mind, we decided to examine Qualcomm’s code in Android devices. During our research, we found multiple privilege escalation vulnerabilities in multiple subsystems introduced by Qualcomm to all its Android devices in multiple different subsystems.
In this presentation we will review not only the privilege escalation vulnerabilities we found, but also demonstrate and present a detailed exploitation, overcoming all the existing mitigations in Android’s Linux kernel to run kernel-code, elevating privileges and thus gaining root privileges and completely bypassing SELinux.