JS_DLOAD.TEYJO

This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users.

It executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system.

Arrival Details

This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users.

Installation

This Trojan creates the following folders:

• %Application Data%\{random}

(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

Download Routine

This Trojan connects to the following website(s) to download and execute a malicious file:

• http://{BLOCKED}asfhasion2017.com.br/7za.exe
• http://{BLOCKED}asfhasion2017.com.br/HN53SL3VBYMC.zip - inaccessible

It saves the files it downloads using the following names:

• %Application Data%\{random string}\7za.exe - (7-Zip tool)
• %Application Data%\{random string}\{random string}.zip

(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

It then executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system.