Threat actors are spreading samples of the Bolik banking Trojan family disguised as a reputable virtual private network (VPN) app.
Researchers at Doctor Web came across the attack campaign and found that it used fake websites of popular software to deliver the Trojan. In one instance, they spotted a spoofed website for the NordVPN service at nord-vpn[.]club. This website arrived with the same design and a similar domain name as NordVPN’s official web location. Like the legitimate website, this fake copy encouraged users to download a program to activate the VPN.
Users who fell for the manufactured lookalike ended up downloading Win32.Bolik.2 onto their machines. This version was an improvement over Win32.Bolik.1, partly because it behaved more like a polymorphic threat containing multiple components. Like its predecessor, however, Win32.Bolik.2 still enabled attackers to perform webinjections, intercept traffic, activate a keylogger and steal information from several bank-client systems.
Disguises Used in Recent Banking Trojan Attacks
Threat actors have a history of disguising banking Trojans to masquerade as legitimate software. In early April 2019, Trend Micro discovered a new XLoader variant that masqueraded as an Android security app.
That was just a week or so before Doctor Web had its first run-in with Win32.Bolik.2. At the time, attackers had compromised the website of a popular video editing software and injected the Trojan into the platform’s download links.
In June 2019, Kaspersky Lab spotted Riltok, a mobile Trojan that masqueraded as apps for popular free ad services in Russia.
How to Defend Against Bolik Campaigns
Security professionals can help defend against a banking Trojan like Bolik by using artificial intelligence capabilities to enhance their automated malware remediation efforts. Companies should also consider investing in a unified endpoint management (UEM) solution that uses compliance rules to automate remediation and automatically removes malware upon discovery from an in-scope endpoint.