Anatsa Banking Trojan Spreading Rampantly Through Google Play Store: All You Need to Know

The dangerous banking trojan, Anatsa, is continuing to spread across countries through Google Play Store. Threat actors are using malware droppers disguised as legitimate mobile apps on the store to distribute the trojan to Android users. The trojan targets over 600 mobile banking applications worldwide and has amassed tens of thousands of installs via the application store in the past few months, per ThreatFabric. Here’s all you need to know about Anatsa banking trojan.

How does Anatsa spread malware?

The malicious apps are disguised as legitimate-looking apps such as PDF viewers, editor apps, and office suites in the office/productivity category. In the latest Anatsa campaign, the malware operators used fake cleaner apps as well as those which promise to free up space on a device by deleting unnecessary files.

ThreatFabric's report highlighted an example of such an app named Phone Cleaner – File Explorer, which marked over 10,000 downloads on the Play Store. Another app called PDF Reader: File Manager also has more than 100,000 downloads, ThreatFabric told BleepingComputer.

Once these malicious apps are installed on the victim's device, the dropper apps request an external resource hosted on GitHub to download the Anatsa payloads disguised as text recognizer add-ons for apps such as Adobe Illustrator. Further, the banking trojan collects financial information such as bank account credentials, credit card details and payment information by employing phishing pages when the user attempts to launch their legitimate bank app.

As per reports, Anatsa targets nearly 600 financial apps of banking institutions from around the world. The trojan uses the stolen information to perform fraud by launching the banking app and performing transactions on the victim's behalf. The money-stealing process is automated and goes completely undetected. The stolen amounts are reportedly converted to cryptocurrency and passed through an extensive network of money mules to avoid detection.

How does Anatsa avoid detection from Google Play?

The malware developers use a multi-staged infection process to avoid detection from the Play Store. The process includes downloading a DEX file from a remote location which retrieves code for executing malicious actions. When the droppers are uploaded to Google Play, they contain nothing that can flag them as suspicious. The fraudulent actions are executed only after the droppers are installed on a device.

Further, according to ThreatFabric, whenever the malicious app was removed from the store, the attackers returned quickly by uploading a new dropper under a new disguise. The report noted that the dropper applications often regularly reach the top 3 new free applications in Google Play.

Rate of infections

The malware-spreading campaign has been going on for over four years and a recent campaign was reportedly launched last year. So far, victims across the European region have downloaded malware droppers over 100,000 times since November. In a previous campaign during the first half of 2023, the malware marked over 130,000 installations of its weaponized droppers for Anatsa from Google's Play Store. In total, Threatfabric estimates the download count to be about 150,000 for Anatsa droppers on Google Play. However, the researchers called it a conservative estimate and stated that the real figure would be closer to 200,000, in a BleepingComputer report.

Countries affected

In the first wave of the campaign, which surfaced in 2020, people across the US, Italy, the United Kingdom, France, Germany, and several other European countries were impacted. Further, as part of the recent campaign that started in November 2023, the attackers expanded their targets to countries like Slovakia, Slovenia, and Czechia.