OSX DoK Malware linked to Operation Emmental used to target Swiss Banks again

Crooks behind the Operation Emmental hacking campaign have started targeting the Swiss banks using a variant of the DoK Mac OS X malware.

In July 2014, malware researchers at Trend Micro published a report on the hacking campaign “Operation Emmental” that was targeting Swiss bank accounts whit a multi-faceted attack that allowed crooks to bypass two factor authentication implemented by the financial organization to protect its customers.

According to the experts, the Operation Emmental has been around since at least 2012.

The experts dubbed the campaign “Operation Emmental” because of the numerous holes in the security implemented by the Swiss banks, exactly like the popular Swiss Emmental cheese.

The hackers used a malware which was able to intercept SMS tokens used to authorize operations and change domain name system settings to hijack victims to rogue bank websites, which were a replica of legitimate ones, used for phishing attacks.

The threat actors targeted bank customers’ accounts in different countries, including in Switzerland, Austria, Japan and Sweden. Investigators suspected that Russian-speaking individuals were responsible for the Operation Emmental due clues discovered in the source code analyzed.

The hackers behind the Operation Emmental have continued to improve their malicious codes. The hackers used on Android malware and a Windows banking Trojan tracked as Retefe and WERDLOD.

The novelty in the operation of the group is represented by the usage of a new variant of the Dok malware in a new wave of attacks against the Swiss banks.

The malicious code is delivered via email, once the DOK malware infects a macOS system, it gains administrative privileges and installs a new root certificate. The root certificate allows the malicious code to intercept all victim’s communications, including SSL encrypted traffic.