The Retefe banking Trojan has resumed its activity with a new series of attack campaigns that leverage Smoke Loader as an intermediate loader.

Proofpoint observed that the malware returned to regular attacks against German and Swiss users in April 2019 after taking a hiatus in 2018. These campaigns helped reveal several new techniques now employed by the banking Trojan. One geographically targeted campaign against Switzerland, for instance, used an Object Linking and Embedding (OLE) package to deliver Smoke Loader. This threat, in turn, downloaded Retefe two hours after infection.

The banking malware incorporated other changes as well. One operation detected by Proofpoint abused a shareware application to run an executable and a Python script. This code, in turn, wrote two files: convert-pdf-to-word-plus.exe and convert-pdf-to-word-plus_driver.exe. The former was a legitimate installer for the Convert PDF to Word Plus application that’s executed as a decoy, while the latter acted as a Retefe loader.

In another campaign, the malware turned away from Tor toward a stunnel, most likely in a bid to cause less noise in an enterprise environment and thereby avoid detection.

Looking to the Past of Retefe

This resurgence of Retefe comes after a busy period several years ago. In June 2016, Avast observed the malware using fake certificates to target U.K. banking customers and steal their login credentials. More than a year later, Proofpoint discovered the banking Trojan leveraging EternalBlue, the same exploit used by WannaCry ransomware, to move laterally through a network following the initial infection of a victim.

How to Defend Against a Banking Trojan

Security professionals can defend against banking Trojans like Retefe by using ahead-of-threat detection to discover potentially malicious domains before threat actors take advantage of them in attacks. Security teams should also use tools such as VBA editor to inspect the macro code in Microsoft Office documents for signs of malicious functionality.

More from

Operational Technology: The evolving threats that might shift regulatory policy

Listen to this podcast on Apple Podcasts, Spotify or wherever you find your favorite audio content. Attacks on Operational Technology (OT) and Industrial Control Systems (ICS) grabbed the headlines more often in 2022 — a direct result of Russia’s invasion of Ukraine sparking a growing willingness on behalf of criminals to target the ICS of critical infrastructure. Conversations about what could happen if these kinds of systems were compromised were once relegated to “what ifs” and disaster movie scripts. But those days are…

Cybersecurity 101: What is Attack Surface Management?

There were over 4,100 publicly disclosed data breaches in 2022, exposing about 22 billion records. Criminals can use stolen data for identity theft, financial fraud or to launch ransomware attacks. While these threats loom large on the horizon, attack surface management (ASM) seeks to combat them.ASM is a cybersecurity approach that continuously monitors an organization’s IT infrastructure to identify and remediate potential points of attack. Here’s how it can give your organization an edge.Understanding Attack Surface ManagementHere are some key…

Six Ways to Secure Your Organization on a Smaller Budget

My LinkedIn feed has been filled with connections announcing they have been laid off and are looking for work. While it seems that no industry has been spared from uncertainty, my feed suggests tech has been hit the hardest. Headlines confirm my anecdotal experience. Many companies must now protect their systems from more sophisticated threats with fewer resources — both human and technical. Cobalt’s 2022 The State of Pentesting Report found that 90% of short-staffed teams are struggling to monitor for…

Hackers are Increasingly Targeting Auto Dealers

Auto dealerships are increasingly concerned with cybersecurity in the face of new regulations and an alarming rise in cyberattacks. The Second Annual Global State of Cybersecurity Report by CDK Global found that 85% of dealerships say cybersecurity is very or extremely important relative to other operational areas. Additionally, 89% say cybersecurity is more important than last year, a 12% increase. Not surprisingly, only 37% of auto retailers are confident in the current protection, which is a 21% decrease from 2021.…