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 September 27th, 2021 (Monday) to October 3rd, 2021 (Sunday).
For the main category, info-stealer ranked top with 63.2%, followed by Downloader with 19.2%, RAT (Remote Administration Tool) malware with 10.7%, Backdoor Downloader with 3.7%, Ransomware with 1.9%, CoinMiner with 1.1%, and Banking malware with 0.2%.
Top 1 – AgentTesla
AgentTesla tied for first place with BeamWinHTTP with 18.4%. It is an info-stealer malware that leaks user information saved in web browsers, e-mails, and FTP clients.
Recently collected samples use the following mail servers and user accounts when leaking the collected information.
sender : aammorris@askoblue[.]com
receiver : aammorris@askoblue[.]com
user : aammorris@askoblue[.]com
pw : offi***2#
sender : chf@segurosramiro[.]com
receiver : chf@segurosramiro[.]com
user : chf@segurosramiro[.]com
pw : Mx]G~~***0q=
sender : message@aust-grp[.]com
receiver : naturesilver@yandex[.]com
user : message@aust-grp[.]com
pw : M2ai6lte4***ka7d8
As most are distributed through spam mails disguised as invoices, shipment documents, and purchase orders, the file names contain such words shown above (Invoice, Shipment, P.O. – Purchase Order). Some samples have extensions disguised as document files such as pdf and xlsx or Auto CAD blueprint files such as dwg.
- 211913490 – BL.exe
- HSBC Payment Advice_PDF.scr
- New Order – N.C.R. Engineering (2).exe
- New Order 86-55113pdf.exe
- Offer-requirement NO. 9-28-2021.exe
- P-list – PO SO-203 (1st Container).exe
- TNT Original Invoice.exe
Top 1 – BeamWinHTTP
BeamWinHTTP is a downloader malware which tied for first place with AgentTesla (18.4% each). 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.
The confirmed C&C server URL is as follows.
Top 3 – Formbook
Formbook is an info-stealer malware ranked third with 10.3%.
Like other info-stealer malware, it is mainly distributed through spam mails. The distributed file names are close to each other.
- September Settlement of Accounts ( USD 13,551.18 ).exe
- (inv 768000 ).exe
- (SW-FM-2021 ).exe
- product specifications.exe
- Purchase Order.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 account information 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 4 – Smoke Loader
Smoke Loader is an info-stealer / downloader malware that ranked fourth place with 9.5%. For analysis report related to Smoke Loader, refer to the ASEC Report below.
The confirmed C&C server URLs are as follows.
Top 5 – Lokibot
This week, Lokibot ranked fifth place 7.3%. It is an info-stealer malware that leaks information about programs such as web browsers, mail clients, and FTP clients.
Being a malware that is distributed through spam mails, it shares similar distributed file names with other malware that are distributed through spam mails.
- For Export to China.exe
- (SW-FM-2021 ).exe
- 321060 Apsun Inc..exe
- 321068 Apsun Inc..exe
- 321768 apsun inc..exe
- 391068 apsun inc..exe
- INVOICE 18083-INV-P.exe
- lista de precios y nueva cotización.PDF.__________________________.bat
- PO 210928-03A.exe
- PO 210930-0032A.exe
- PO 290921-021A.exe
- po 290929-021a.exe
- SMK_15587 90426.exe
As shown in the below, most Lokibot C&C server URLs tend to end in fre.php.
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