Security firm RiskIQ has identified a new threat actor that is allegedly behind an online network that is delivering scam advertisements from thousands of different domain names. In a report titled, “NoTrove: The Threat Actor Ruling a Scam Empire” RiskIQ details the activities of the NoTrove campaign, which makes use of automation to stay a step ahead of defenders.
William MacArthur, a threat researcher at RiskIQ explained to eWEEK that the NoTrove attackers operate in a grey area of activity by delivering scams and fraudulent landing pages that are often ignored by typical detection tools that are looking for traditional “malvertising.”
“NoTrove is part of the digital advertising ecosystem and it’s just a big mess that doesn’t really need to be out there,” MacArthur said.
NoTrove operates at a large scale making use of 2,000 randomly generated domain names and over 3,000 IP addresses. Though the domain names used in the NoTrove campaign are often short-lived, RiskIQ reported that one domain controlled by NoTrove had a ranking of 517 on the Alexa list of the top 10,000 sites on the internet.
To date, RiskIQ has detected 78 different variants of NoTrove campaigns, including fake software downloads and scam survey awards. The NoTrove campaign has multiple stages, with the first stage being some form of redirection. The second stage delivers a scam payload or a Potentially Unwanted Program (PUP) to the end-user victim. If there is no payload for a specific NoTrove campaign, there is a fallback method that delivers a different ad from a secondary network.
“Traffic is an essential commodity for legitimate web companies and criminal underground economy alike,” the RiskIQ report states. “Everyone wants a piece of the traffic pie, and NoTrove is feasting.”
The attackers behind NoTrove are buying ad space on publisher sites that use real time bidding systems to fill inventory. MacArthur said that the cyber-attackers are often buying placement inventory for pennies and then profiting with various scams. Though MacArthur said that NoTrove is a profitable operation, at this point he doesn’t have any specific figures he can share on the actual financial impact of the fraud activities. That said, he noted that scam ads will lead to an increased use of ad blockers by end-users, which will have a negative impact on the online media business.
Other security vendors have reported on other aspects of online media fraud campaigns in recent years. In December 2016, security firm WhiteOps detailed its investigation into an advertising fraud network called ‘Methbot’ that was allegedly responsible for up to $5 million in fraud every day.
