TROJ_WERDLOD.D

This online banking Trojan modifies an affected system's proxy settings and adds a malicious root certificate to allow information theft at the network level. These behaviors are seen in malware used in Operation Emmental.

To get a one-glance comprehensive view of the behavior of this Trojan, refer to the Threat Diagram shown below.

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It does not have any propagation routine.

It does not have any backdoor routine.

As of this writing, the said sites are inaccessible.

Arrival Details

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This Trojan drops the following file(s)/component(s):

• %All Users Profile%\cert{value}.der - install certificate on trusted root certificate store, will be deleted after
• %User Temp%\{random filename}.txt ← saves gathered cookies content

(Note: %All Users Profile% is the All Users folder, where it usually is C:\Documents and Settings\All Users on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\ProgramData 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.. %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp 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.)

Other System Modifications

This Trojan modifies the following file(s):

• {firefox path}\prefs.js

It adds the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings
AutoConfigURL = "http://{BLOCKED}.{BLOCKED}6.200.228:8080/proxy.pac"

Propagation

This Trojan does not have any propagation routine.

Backdoor Routine

This Trojan does not have any backdoor routine.

Download Routine

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

• http://{BLOCKED}bunko.org/wp/wp-content/themes/twentyfourteen/images/vrucimeirxeimurixeuri.exe

It saves the files it downloads using the following names:

• %All Users Profile%\Microsoft-KB{random}.exe ← detected as TROJ_DOFOIL.UKL

(Note: %All Users Profile% is the All Users folder, where it usually is C:\Documents and Settings\All Users on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\ProgramData 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.)

As of this writing, the said sites are inaccessible.

NOTES:

This Trojan downloads Windows PoweSshell installer and installs it if the said Windows component is not existing.

It connects to the following to update count hits:

• http://www.{BLOCKED}ycounter.com/counter.php?vtrtvrvtrtvertvr
• http://www.{BLOCKED}ycounter.com/counter.php?tcrcrcerererwbvbbrtdf

It checks for the following processes:

• VBoxService
• VBoxTray
• Proxifier
• prl_cc
• prl_tools
• vmusrvc
• vmsrvc
• vmtoolsd

It checks for specific list of domains in browser cookies and browser history. When accessing specific domains, users access the malicious SOCKS server using the file from the following:

• http://{BLOCKED}.{BLOCKED}6.200.228:8080/proxy.pac

The modified prefs.js contains the following:

• user_pref(network.proxy.type.2)
• user_pref(network.proxy.autoconfig_url http://{BLOCKED}.{BLOCKED}.200.228:8080/proxy.pac)

It terminates the following processes:

• chrome.exe
• firefox.exe
• iexplore.exe

It imports rogue root certificates to browsers Internet Explorer and Firefox.