Researchers monitoring the Emotet botnet have noticed that malware has begun to push the QakBot banking trojan at an unusually high rate, replacing the TrickBot payload it has been using for years.
Last week, Emotet returned to active action after a five-month hiatus. As of yesterday, the operation of malspam started for a while the installation of TrickBot on violated Windows systems.
Things changed today when researchers noticed that Emotet was spreading QakBot. A string in the malware indicates that this trojan is now the partner that chose the Emotet botnet.
A team of researchers and system administrators who have come together to fight Emotet companies called Cryptolaemus, saw today that the menacing factor replaced the TrickBot distribution in all "epochs".
An Emotet epoch is a subset of the botnet that operates on a separate infrastructure. Currently, there are three of them, each with separate ones servers orders and control, distribution methods and payloads.
Speaking to BleepingComputer, the Cryptolaemus team said it saw QakBot distributed throughout Emotet's botnet, as TrickBot was completely absent.
A security researcher named Bom spotted a sample of QakBot (QBot) malware and "passed it on" to the interactive analysis tool Any.Run. Results are available on this link. A list of command and control server addresses (C2) is available here.
Additional analysis by cybercrime intelligence company Intel 471 revealed that the string for this QBot campaign is "partner01", indicating a strong connection between Emotet and these threats.
However, drawing quick conclusions about the non-cooperation of Emotet and TrickBot is not safe as the relationship between these two operators is not exclusive. The Cryptolaemus team said the change to one payload has happened in the past and that the original duo is very likely to continue their collaboration.
However, this does not happen very often. For example, Emοtet started using QakBot last year.
TrickBot and QakBot are the preferred partners for Emotet. All three hackers are part of the same Russian-speaking community and have been interacting for a long time.
It is not clear what QakBot distributes to infected systems, but some victims may fall victim to ransomware.
To learn more about Emotet campaigns, you can follow Cryptolaemus's Twitter profile.
Even though there is a different payload, Emotet still relies on emails to distribute malware, with threatening to be delivered via some malicious document.