Tag: TrojanPasswordStealer

Trojan Agent Tesla – Malware Analysis

Anurag Gawande4 Comments

Hash – 077f75ef7fdb1663e70c33e20d8d7c4383fa13fd95517fab8023fce526bf3a25

Family : Agent Tesla

Downloaded Sample Link: Click here

Signature: Microsoft Visual C# v7.0/ Basic.NET

Filename: UIhLdVHHlUAKoEOpjVAsXFlIQrgS.exe

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VirusTotal score:

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Malware behavior:

  • Steal browser information (URL, Usernames, Passwords)
  • Steal passwords for email clients.
  • Steal FTP Clients
  • Steal download manager passwords.
  • Collect OS and hardware information.

Browser Information:

When I debug the malware executable, Initially it creates a SQLite database to store collected information from victims machine.

Below are the tables getting created.

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Tables created:

  • meta
  • logins
  • sqlite_sequence
  • stats
  • compromised_credentials

found it collected browsers data (Google chrome), that includes accessed URLs and related usernames and passwords.

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database table logins stores all browser related information. Below are the table columns.

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Apart from this, malware also look for all different types of browsers to steal data from it.

It look for below browsers:

  • Opera Browser
  • Yandex Browser
  • 360 Browser
  • Iridium Browser
  • Comodo Dragon
  • Cool Novo
  • Chromium
  • Torch Browser
  • 7Star
  • Amigo
  • Brave
  • CentBrowser
  • Chedot
  • Coccoc
  • Elements Browser
  • Epic Privacy
  • Kometa
  • Orbitum
  • Sputnik
  • Uran
  • Vivaldi
  • Citrio
  • Liebao Browser
  • Sleipnir 6
  • QIP Surf
  • Coowon
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Below screenshot taken while debugging malware.

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Malware also look for below email clients. I haven’t install any of them on my machine during analyzing this.

Email Clients:

  • Outlook
  • Thunderbird
  • Foxmail
  • Opera Mail
  • Pocomail
  • Claws-mail
  • Postbox
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FTP Clients:

Malware grabs credentials from FTP clients as well. Below list.

  • FileZilla
  • Core FTP
  • SmartFTP
  • FTPGetter
  • FlashFXP
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It also makes FTP web request. (Remote Server couldn’t find)

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It uses smtp client to send information over the network using port 587 which indicates sending data from smtp client to a particular smtp Server through mail attachments.

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Malware executable also make HTTPWebRequest which must be downloading SMTP client to transfer data to remote SMTP server.

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unfortunately, it didn’t make any connection to any remote server address.

Summary:

  • Steal Browser Information including urls, usernames and passwords.
  • Steal email client credentials.
  • Steal credentials of FTP servers.
  • Computer information.

Thank you.

Password stealer Trojan – Malware Analysis

Anurag Gawande3 Comments

Hi Visitor, I got this sample of malware shared on VirusBay.

Sample below:

SHA256: 630efa1e2dc642799b867363bb36d1953884480ac29942a1ab20243a8a9620ad

Signature: Microsoft Visual C# v7.0/ Basic .Net and its a Windows forms application.

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Upon execution, this file drops below two files at location C:\Users\<UserProfile>\AppData\Local\Temp\

Dropped files:

C:\Users\<UserProfile>\AppData\Local\Temp\FB_2C02.tmp.exe

C:\Users\<UserProfile>\AppData\Local\Temp\cc3a68ce1dad95ce662e1c51568e3a.exe (Application Server)

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Upon execution of this file, it take a screenshot of current screen and save at C:\Users\<UserProfile>\AppData\Local\Temp location.

Also it adds below file to startup programs.

  • cc3a68ce1dad95ce662e1c51568e3a.exe (Application Server)
  • And main malware sample file.
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FB_2C02.tmp.exe:

SHA256: A02CF7E4D01C3E04C0C6F723A541289A12C5D87ECC47F6B675D84A6B1B0A23B3

File description: Gomorrah

Signature: Microsoft Visual C# v7.0/ Basic .Net and its a Windows forms application.

I used ILSpy decompiler to decompile FB_2C02.tmp.exe. I could see the functions written to achive below purpose.

Purpose:

  1. Steal browser saved user account information.
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I used google chrome on which VM i was doing analysis. I could see this file has created a Passwords.txt file at C:\Users\<UserProfile>\AppData\Local\Temp\Passwords.txt

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Decomplied code of executable which grab google chrome url, username and password.

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2. System Information.

This file also located at C:\Users\<UserProfile>\AppData\Local\Temp

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3. Outlook Password.

This file also located at C:\Users\<UserProfile>\AppData\Local\Temp. As I wasnt using outlook, the file was empty.

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4. Credit Card information

This file CC.txt which stores information about CC also located at C:\Users\<UserProfile>\AppData\Local\Temp.

It was empty too.

Below code grab CC information from the browser.

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Just not from Google chrome but from all below,

  • Amigo
  • Brave
  • Kometa
  • Orbitium
  • Totch
  • Yandex
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It uploads all collected to the remote location. Though I am not able to see it is connecting to remote server anymore because when I ran this, got run time exceptions.

But it gets connected to below URL as its mentioned on VirusTotal detection.

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Summary:

Malware upload below information to remote server.

  • Web account passwords from web browsers.
  • Credit card information from web browser.
  • Outlook passwords.
  • Client machine information.

Thank you.