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 December 6th, 2021 (Monday) to December 12th, 2021 (Sunday).
For the main category, info-stealer ranked top with 33.3%, followed by CoinMiner with 25.3%, Downloader with 22.8%, RAT (Remote Administration Tool) malware with 16.2%, Banking malware with 1.8%, and Ransomware with 0.6%.
Top 1 – Glupteba
Glupteba is a malware developed with Golang, taking first place with 25.33%. It downloads various additional modules and has various features, but it is actually a CoinMiner malware that installs XMR (Monero) CoinMiner.
When Glupteba is executed, it acquires the system permission by going through UAC Bypass and using TrustedInstaller’s permission. It then disguises as a normal process named C:Windows\rsscsrss.exe and remains in the system. Afterward, Glupteba downloads additional modules such as rootkit drivers for a purpose of concealing processes and files, and ultimately installs Eternal Blue package to spread through XMR CoinMiner and SMB vulnerabilities.
So far, most of the confirmed Glupteba samples are being downloaded and distributed via PUPs. Even though Glupteba is being distributed via PUP, it takes the appearance of a MalPe packer (it is mentioned in the previous blog post).
Malware strains that take the appearance of a MalPe packer usually are distributed via Exploit Kit, but like previous cases of Vidar infostealer, malware downloaded via PUP and malware distributed by disguising as a normal program also had the appearance of a MalPe packer.
The C&C URL confirmed are as follows.
[C&C Server URL]
Top 2 – BeamWinHTTP
BeamWinHTTP is a downloader malware that ranked second with 21.6%. BeamWinHTTP is distributed via malware disguised as PUP installer. When it is executed, it installs PUP malware Garbage Cleaner, and can download and install additional malware at the same time.
Recently, there have been numerous cases of distribution by the dropper disguised as a software crack file. The ASEC analysis team is responding to this malware using the alias ‘MulDrop.’ See the following blog post for more information on the malware.
The confirmed C&C server URL is as follows.
Top 3 – RedLine
RedLine malware ranked third place with 12.2%. The malware steals various information such as web browsers, FTP clients, cryptocurrency wallets, and PC settings. It can also download additional malware by receiving commands from the C&C server. Like BeamWinHTTP, there have been numerous cases of RedLine being distributed under the disguise of a software crack file.
The following are the confirmed C&C server domains for RedLine:
Top 4 – Formbook
Formbook is an info-stealer malware that ranked fourth place with 11.6%.
Like other info-stealer malware, it is mainly distributed through spam emails. The distributed file names are close to each other.
- Tax payment invoice – Wednesday, December 8, 2021,pdf.exe
- Products List & purchase document.exe
- wanted list.exe
- PURCHASE_ORDER MT101 & PRODUCT LIST.exe
- PO 211206-01A.exe
As Formbook is injected in a normal process that is in the directory of explorer.exe and system32, the malicious behaviors are performed by the normal process. Besides user credentials in the web browser, the malware can steal various information through keylogging, clipboard grabbing, and web browser form grabbing.
Below is the list of confirmed C&C server URLs of Formbook.
Top 5 – AgentTesla
AgentTesla was ranked fifth place with 9.8%. It is an info-stealer malware that leaks user credentials saved in web browsers, emails, and FTP clients.
Recently collected samples use the following email servers and user accounts when leaking the collected information.
- FTP Server : ftp://ftp.gene[.]ba
user : dod@gene[.]ba
password : bo*****56
- SMTP Server : mail.faiyazgroup[.]com (
sender : jahangir@faiyazgroup[.]com
receiver : jahangir@faiyazgroup[.]com
password : jah*****56
- SMTP Server : mail.scsgroups[.]com (
sender : sales@scsgroups[.]com
receiver : sales@scsgroups[.]com
password : Sc******123
- SMTP Server : smtp.yandex[.]com (
sender : vladmir@amova[.]ga
receiver : vladmir@amova[.]ga
password : mar******360
- SMTP Server : us2.smtp.mailhostbox[.]com (
sender : firstname.lastname@example.org[.]in
receiver : email@example.com[.]in
password : 22*****69
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.
- Urgent Bank Details Confirmation,pdf.exe
- TT Swift copy (2).exe
- request for quotation.exe
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