The ASEC analysis team is using the ASEC automatic analysis system RAPIT to categorize and respond to known malware. This post will list weekly statistics collected from August 8th, 2022 (Monday) to August 14th, 2022 (Sunday).
For the main category, info-stealer ranked top with 41.9%, followed by backdoor with 38.4%, downloader with 16.8%, ransomware with 2.2%, and CoinMiner with 0.6%.
Top 1 – Agent Tesla
AgentTesla is an infostealer that ranked first place with 23.1%. It is an info-stealer that leaks user credentials saved in web browsers, emails, and FTP clients.
It uses e-mail to leak collected information, and there are samples that used FTP or Discord API. C&C information of recently collected samples is as follows.
server : mail.dyreco[.]com (185.161.97[.]12)
sender : email@example.com
receiver : firstname.lastname@example.org
user : email@example.com
pw : Dy*******11server :mail.pioneerentp.com (66.117.3[.]103)
sender : firstname.lastname@example.org
receiver : email@example.com
user : firstname.lastname@example.org
pw : Ran******Mbserver :mail.activandalucia.com (185.162.171[.]75)
sender : email@example.com
receiver : firstname.lastname@example.org
user : email@example.com
pw : iy*******6789@$
As most are distributed through spam emails disguised as invoices, shipment documents, and purchase orders, the file names contain such words shown above (Invoice, Shipment, P.O. – Purchase Order). Multiple collected samples were disguised as files with extensions of pdf and xlsx.
9823581_pdf.exeEPDA.exePO-151.exerevised order_pdf.exedocuments.exeINQUIRY 6000912781_PDF.exeKW-289-2022-Oil immertsion Heater.exeImage $95,934.55.exeWMp2DHcMCHOfAYS.exe
Top 2 – Remcos
This week, Remcos ranked second place with 14.9%. Remcos is a RAT malware that carries out various commands given by the attacker such as keylogging and information leaking.
Remcos is packed with a .NET packer and is distributed as attachments to spam emails, just like AgentTesla, Formbook, and NanoCore.