Security researchers observed attackers using unofficial webpages in an attempt to target Russian financial institutions with the Geost banking Trojan.

By reverse engineering a sample of Geost, Trend Micro learned that digital attackers primarily relied on unofficial webpages with randomly generated server hostnames to distribute the banking Trojan. As such, the malware specifically targeted Android users without access to the Google Play store and those inclined to search for programs not available on Google’s official Android marketplace.

One sample discovered by Trend Micro arrived in an application with the name “установка,” which is Russian for “setting.” The app used the Google Play logo to trick users into downloading it from an obscure web server. Unsurprisingly, this program hid its logo upon successful installation. It then demanded that its victims grant it important administrator privileges, including the ability to access SMS messages for the purpose of receiving confirmation text messages from Russian banking services.

Other Malware Threats Confronting Russian Banks

Geost first attracted the security community’s attention in October 2019. At that time, Virus Bulletin published a research paper detailing the activities of the Trojan. This briefing revealed that the malware had infected 800,000 victims at the time of discovery.

It’s important to note that Geost isn’t the first banking Trojan that’s targeted Russian financial institutions. Back in June 2019, for instance, Kaspersky Lab discovered that new variants of the Riltok Trojan family had expanded beyond their normal scope of Russian banks to include organizations in France, Italy and the United Kingdom.

How to Defend Against the Geost Banking Trojan

Security professionals can help their organizations defend against the Geost banking Trojan and similar threats by preventing employees from downloading apps from unofficial marketplaces onto their work devices. Infosec personnel should also invest in a unified endpoint management (UEM) solution for the purpose of automatically uninstalling infected mobile apps upon detection.