The recent key reinstallation attacks (KRACK) against the WPA2 protocol revealed how an adversary can easily eavesdrop, and in some cases
tamper, a Wi-Fi connection secured by the WPA2 protocol. At the same
time, Wi-Fi automatic association attacks achieve a similar result
(man-in-the-middle position) not by attacking the WPA2 protocol directly
but by enforcing Wi-Fi clients to join a rogue Access Point.
Google promotes the SafetyNet Attestation API as a tool to query and assess the integrity status of an
Android device. The official documentation, leaves no doubt that the main purpose of the
SafetyNet Attestation API is to provide device integrity information to
the server counterpart of mobile applications. The server counterpart may choose to limit the functionalities
available to an app, if it's running on a device with compromised integrity protections.
However, in the past year CENSUS has performed a number of assessments to mobile apps
where SafetyNet was also used as an application integrity security check.
Furthermore, best practices documents such as ENISA's "Smartphone Secure Development Guidelines" document of December 2016, clearly propose the use of SafetyNet as a measure to check an app's integrity status (see page 23).
To the best of our knowledge, Google has not publicly released any detailed official documentation
or recommended the use of the SafetyNet Attestation API for application integrity purposes.
About four months ago (April 2017), Vasilis Tsaousoglou and myself presented our work on exploiting Android's libc allocator at the 2017 INFILTRATE conference (Miami, Florida). Since version 5.0, Android has adopted the jemalloc allocator as its default libc malloc(3) implementation. For our talk we extended our previously released jemalloc heap exploration and exploitation tool called 'shadow' to support Android (both ARM32 and ARM64), and demonstrated its use on understanding the impact of libc heap corruption vulnerabilities. We also presented new jemalloc/Android-specific exploitation techniques for double free and arbitrary free vulnerabilities.