Macro Malware Resurgence Highlighted By Kasidet Outbreak

The Neutrino bot is getting a new boost of rejuvenation from a retro form of distribution that's been making a huge comeback lately. According to research last week out from Zscaler, Neutrino--also known as Kasidet--has spiked again in the wild with the help of malicious Microsoft Office macros. This latest example of VBA-related malware is another piece of evidence that a once forgotten class of malware has roared back to life in the last 18 months.

The delivery of Kasidet backdoors is the continuation of a months-long series of campaigns to drop the Dridex banking malware on victim computers using malicious macros, Zscaler reseachers say.

"Over the past two weeks we are seeing these malicious VBA macros leveraged to drop Kasidet backdoor in addition to Dridex on the infected systems," Zscaler's researchers wrote. "These malicious Office documents are being spread as an attachment using spear phishing emails."

The variant of Kasidet identified in this latest campaign features two main information-stealing features. The first is through browser hooking. And the second is through the point-of-sale (POS) system memory scraping functionality Kasidet is starting to increasingly employ. Once known primarily for its distributed denial-of-service (DDoS) arsenal, its POS targeting features began popping up in earnest last spring.

"Upgrading old malware to include PoS RAM-scraping capabilities is a new technique in the threat landscape, but it’s not surprising given how lucrative stolen payment card data is. It shows that more and more cybercriminals are putting two and two together to make more money," wrote TrendMicro researchers  in an explanation last fall of the phenomenon.

Zscaler researchers say that the inclusion of Kasidet in an ongoing push for Dridex shows how much cyber crooks share underlying infrastructure and delivery mechanisms. As such, infosecurity professionals should expect to see more macro malware in 2016.

According to the most recent McAfee Labs Threat Report Office macro malware has reached a crescendo over the last 18 months. Barely making a dent  in 2013, it started coming back gradually in 2014 until it spiked at the end of that year. Since then, criminals have been on a tear taking advantage of macro vulnerabilities. At the end of third quarter in 2015, year over year growth in macro threats tripled. And McAfee says it has reached its highest level since 2009.