TSPY_ZBOT.THOIBDAI

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

It is injected into all running processes to remain memory resident.

It steals certain information from the system and/or the user.

However, as of this writing, the said sites are inaccessible. It deletes the initially executed copy of itself.

Arrival Details

This Trojan Spy 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 Spy drops the following copies of itself into the affected system and executes them:

• %Application Data%\{second deepest directory path}\{random filename}

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, and 8.)

It is injected into all running processes to remain memory resident.

It adds the following mutexes to ensure that only one of its copies runs at any one time:

• Local\{GUID}
• Global\{GUID}

Other System Modifications

This Trojan Spy adds the following registry keys:

HKEY_CURRENT_USER\Software\Microsoft\
{random registry key name}

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\PhishingFilter

It adds the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\PhishingFilter
EnabledV8 = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings
WarnonBadCertRecving = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings
EnableSPDY3_0 = "0"

HKEY_CURRENT_USER\Software\Microsoft\
{random registry key name}
{random registry entry name} = "{hex value}"

Dropping Routine

This Trojan Spy drops the following files:

• %User Temp%\tmp{random}.bat - Used to delete initially executed copy of itself
• %Application Data%\{deepest directory path}\{random filename 1}.{random file extension 1}
• %Application Data%\{deepest directory path}\{random filename 2}.{random file extension 2}

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, and 8.. %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, and 8.)

Information Theft

This Trojan Spy accesses the following site to download its configuration file:

• http://{BLOCKED}y.su/anime.jpg
• http://{BLOCKED}p.su/girls.jpg

It steals the following information:

• Data on cookie files (URLs)
• Email-related information such as account names, email addresses, passwords, server data, and server port
• Email information stored in the user's Windows Address Book (WAB) file
• Online banking credentials
• Personal digital certificate

It gathers the following account information from any of the mentioned File Transfer Protocol (FTP) clients or file manager software:

• FAR Manager FTP
• FTPWare
• Total Commander

Other Details

This Trojan Spy connects to the following URL(s) to check for an Internet connection:

• http://{BLOCKED}x.ru/

It does the following:

• Receive configuration file.
  The received configuration file may contain URLs where it downloads an updated copy of itself and where it sends its gathered information. It may also contain URLs of its target online banking and finance-related sites from where it steals the information. Note that the contents of the file, hence the list of websites to monitor, may change anytime.
• The random file names used by the Trojan Spy is based on files located in the %Application Data% directory of the affected machine

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, and 8.)

However, as of this writing, the said sites are inaccessible.

It deletes the initially executed copy of itself