September 29, 2023

A cybersecurity agency says a well-liked Android display screen recording app that racked up tens of hundreds of downloads on Google’s app retailer subsequently started spying on its customers, together with by stealing microphone recordings and different paperwork from the person’s telephone.

Analysis by ESET discovered that the Android app, “iRecorder — Display screen Recorder,” launched the malicious code as an app replace nearly a yr after it was first listed on Google Play. The code, in response to ESET, allowed the app to stealthily add a minute of ambient audio from the system’s microphone each quarter-hour, in addition to exfiltrate paperwork, net pages and media recordsdata from the person’s telephone.

The app is no longer listed in Google Play. In case you have put in the app, it is best to delete it out of your system. By the point the malicious app was pulled from the app retailer, it had racked up greater than 50,000 downloads.

ESET is asking the malicious code AhRat, a personalized model of an open-source distant entry trojan referred to as AhMyth. Distant entry trojans (or RATs) benefit from broad entry to a sufferer’s system and might typically embrace distant management, but additionally perform equally to spyware and adware and stalkerware.

A screenshot of iRecorder, the affected app, in Google Play as it was cached in the Internet Archive in 2022.

A screenshot of iRecorder listed in Google Play because it was cached within the Web Archive in 2022. Picture Credit: TechCrunch (screenshot)

Lukas Stefanko, a safety researcher at ESET who found the malware, said in a blog post that the iRecorder app contained no malicious options when it first launched in September 2021.

As soon as the malicious AhRat code was pushed as an app replace to current customers (and new customers who would obtain the app immediately from Google Play), the app started stealthily accessing the person’s microphone and importing the person’s telephone information to a server managed by the malware’s operator. Stefanko stated that the audio recording “match inside the already outlined app permissions mannequin,” provided that the app was by nature designed to seize the system’s display screen recordings and would ask to be granted entry to the system’s microphone.

It’s not clear who planted the malicious code — whether or not the developer or by another person — or for what purpose. TechCrunch emailed the developer’s e-mail handle that was on the app’s itemizing earlier than it was pulled, however has not but heard again.

Stefanko stated the malicious code is probably going a part of a wider espionage marketing campaign — the place hackers work to gather data on targets of their selecting — generally on behalf of governments or for financially motivated causes. He stated it was “uncommon for a developer to add a reputable app, wait nearly a yr, after which replace it with malicious code.”

It’s not unusual for unhealthy apps to slide into the app shops, neither is it the primary time AhMyth has crept its way into Google Play. Each Google and Apple display screen apps for malware earlier than itemizing them for obtain, and generally act proactively to drag apps once they may put customers in danger. Final yr, Google said it prevented greater than 1.4 million privacy-violating apps from reaching Google Play.