Security researchers from different teams all over the world routinely carry out tests on products consumed by the masses to find out things like their security, reliability, durability etc. The mobile industry is no different in this regard. In one of these tests, researchers have discovered a flaw in a MediaTek chip that is used in over a third of the world’s smartphones that, when taken advantage of, could potentially be used to listen in on private conversations.
This specific chip under scrutiny is an audio processing chip manufactured by MediaTek that is found in a wide range of Android smartphones from different manufacturers including Xiaomi, Oppo, Realme and Vivo.
The researchers, in their official statement, say that if left unpatched, a malicious hacker could theoretically explore the vulnerabilities on the chip to eavesdrop on Android users and could even hide malicious code.
The vulnerability was discovered by researchers from Check Point Research (CPR), who reverse-engineered MediaTek’s audio chip and thereby discovered an opening that could allow a malicious app to install code meant to intercept audio passing through the chip. Once the audio is intercepted, the attacker would then have the freedom of recording it locally or uploading it to their own server.
Upon discovery of the vulnerabilities, the research group forwarded their findings to MediaTek and Xiaomi several weeks ago and the identified vulnerabilities, which currently stand at four, have been reportedly patched by Xiaomi.
Details on the first identified vulnerability have been published in MediaTek’s October 2021 Security Bulletin, while information regarding the fourth vulnerability will be released later in December.
“MediaTek is known to be the most popular chip for mobile devices,” Slava Makkaveev, a security researcher at Check Point Software, says.
“Given its ubiquity in the world, we began to suspect that it could be used as an attack vector by potential hackers. We embarked research into the technology, which led to the discovery of a chain of vulnerabilities that potentially could be used to reach and attack the audio processor of the chip from an Android application.”
At the time of writing, it looks like the researchers from Check Point Research discovered the vulnerability before any malicious hacker could take advantage of it.
Makkaveev, however, could not help but wonder whether there is a possibility the flaw is not really a flaw but a means by which manufacturers could create a listening campaign on their customers. Harvesting data directly from customers in this manner is definitely invaluable to these kinds of companies who would like to know their customer trends. Makkaveev, however, said that his firm did not find any evidence that this is what the aforementioned companies have been doing.
Tiger Hsu, who is a product security officer at MediaTek also said that the company has no reason to think that the vulnerability has already been exploited but also added that they worked quickly to verify the problem and ensured that the necessary patches were available to all device manufacturers who rely on MediaTek’s audio processors.