Mobile Device Management (MDM) solutions are used to centrally manage mobile devices in corporate environments. This includes the monitoring of the device, automatic installation/removal of apps or certificates and restrict the functionality. Even though MDM solutions exist for multiple vendors, we will look specifically on Apple devices enrolled via Intune. When an Apple device is registered for Automated Device Enrollment (ADE), it will automatically download and apply these policies during the initial setup and prior to the first boot.
In this post, we are discussing a bug we came across in Mesas llvmpipe Gallium3D graphics driver. This bug was accessible through Chromium’s WebGL implementation and can provide control of the program counter (pc) within Chromium’s GPU process if llvmpipe is used. Llvmpipe is a software rasterizer that is used on Linux if no hardware acceleration (graphics card) is available. This is a pretty rare edge case as llvmpipe has no widespread use. An estimate by Google is that approx 0.06% of the Chromium users are affected by this. However, as this is a simple but valid Chromium bug, we want to give you a quick walkthrough. The issue is tracked as CVE-2021-21153 and was fixed in February 2020.
Nowadays, Bluetooth is an integral part of mobile devices. Smartphones interconnect with smartwatches and wireless headphones. By default, most devices are configured to accept Bluetooth connections from any
nearby unauthenticated device. Bluetooth packets are processed by the Bluetooth chip (also called a controller), and then passed to the host (Android, Linux, etc.). Both, the firmware on the chip and the host Bluetooth subsystem, are a target for Remote Code Execution (RCE) attacks.
One feature that is available on most classic Bluetooth implementations is answering over Bluetooth pings. Everything an attacker needs to know is the device’s Bluetooth address. Even if the target is not discoverable, it typically accepts connections if it gets addressed. For example, an attacker can run l2ping, which establishes an L2CAP connection and sends echo requests to the remote target.
In the following, we describe a Bluetooth zero-click short-distance RCE exploit against Android 9, which got assigned CVE-2020-0022 . We go through all steps required to establish a remote shell on a Samsung Galaxy S10e, which was working on an up-to-date Android 9 when reporting the issue on November 3 2019. The initial flaw used for this exploit is still present in Android 10, but we utilize an additional bug in Bionic (Android’s libc implementation), which makes exploitation way easier. The bug was finally fixed in the security patch from 1.2.2020 in A-143894715. Here is a demo of the full proof of concept:
