Android Phones Have Security Holes In MediaTek Components

Security gaps in numerous smartphone chips ensured that many Android users could be spied on using their devices. The risks will probably remain in many cases, since entry-level models, in particular, are rarely updated.

Three of the vulnerabilities noted in the security databases under the IDs CVE-2021-0661, CVE-2021-0662, and CVE-2021-0663 concerned the firmware of the MediaTek Digital Signal Processors (DSPs). This is responsible for converting analog audio signals into digital information and vice versa. The vulnerabilities allow attackers to latch onto this interface and listen to phone calls and voice messages.

A fourth vulnerability (CVE-2021-0673) was also found in a MediaTek component, such as the security researchers at Check Point to report. The Hardware Abstraction Layer (HAL) of the audio processing was affected here. This also gave attackers access to information that is otherwise relatively well shielded. The four security holes made it possible to obtain the signals mentioned without having to interact with the user, which is the case with most malware that attacks the installed Android system.

Several systems affected

One of the problems with weak points in such components is that they affect a significantly larger group of users than the frequently changed core areas of a smartphone SoC. As long as these small components work, there is little need to lend a hand with every new SoC generation, so that a weak point can often be found for a long time and in a correspondingly large number of chips.

MediaTek chips have a share of around 40 percent in the smartphone market, and the provider’s SoCs are also increasingly found in higher-quality models. The weak points in the inexpensive entry-level devices are particularly problematic. Because even if these are supplied with patches by their manufacturers, they are often used by technically less experienced users who also rarely update the operating system. However, MediaTek is already delivering patches for the three DSP holes, and the fourth bug is to be dealt with in December.