TSPY_ZBOT.ULJ

September 20, 2013
 Analysis by: Andrei Castillo
 PLATFORM:

Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:
 INFORMATION EXPOSURE:

  • Threat Type: Spyware

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

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

  TECHNICAL DETAILS

File Size:

462,848 bytes

File Type:

EXE

Memory Resident:

Yes

Arrival Details

This spyware 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 spyware drops the following copies of itself into the affected system:

  • %Application Data%\{random folder name}\{random file name}.exe

(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 and 7.)

Autostart Technique

This spyware adds the following registry entries to enable its automatic execution at every system startup:

HKEY_CURRENT_USER\Software\Microsoft\
WIndows\CurrentVersion\Run
{random value} = "%Application Data%\{random folder name}\{random file name}.exe"

It drops the following files:

  • %Application Data%\Microsoft\Address Book\{Username}.wab

(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 and 7.)

Other System Modifications

This spyware adds the following registry keys:

HKEY_CURRENT_USER\Software\Microsoft\
{random}

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Active Directory GC

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Bigfoot

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\VeriSign

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\WhoWhere

HKEY_CURRENT_USER\Software\Microsoft\
WAB\WAB4

HKEY_CURRENT_USER\Software\Microsoft\
WAB\WAB4\WAB File Name

It adds the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
{random}
{random values} = {random hex or string values}

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager
Server ID = "4"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager
Default LDAP Account = "Active Directory GC"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts
PreConfigVer = "4"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts
PreConfigVerNTDS = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Active Directory GC
LDAP Server ID = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Active Directory GC
Account Name = "Active Directory"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Active Directory GC
LDAP Server = "NULL"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Active Directory GC
LDAP Search Return = "64"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Active Directory GC
LDAP Timeout = "3c"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Active Directory GC
LDAP Authentication = "2"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Active Directory GC
LDAP Simple Search = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Active Directory GC
LDAP Bind DN = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Active Directory GC
LDAP Port = "cc4"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Active Directory GC
LDAP Resolve Flag = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Active Directory GC
LDAP Secure Connection = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Active Directory GC
LDAP User Name = "NULL"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Active Directory GC
LDAP Search Base = "NULL"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Bigfoot
LDAP Server ID = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Bigfoot
Account Name = "Bigfoot Internet Directory Service"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Bigfoot
LDAP Server = "ldap.bigfoot.com"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Bigfoot
LDAP URL = "http://www.bigfoot.com"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Bigfoot
LDAP Search Return = "64"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Bigfoot
LDAP Timeout = "3c"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Bigfoot
LDAP Authentication = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Bigfoot
LDAP Simple Search = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\Bigfoot
LDAP Logo = {random hex values}

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\VeriSign
LDAP Server ID = "2"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\VeriSign
Account Name = "VeriSign Internet Directory Service"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\VeriSign
LDAP Server = "directory.verisign.com

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\VeriSign
LDAP URL = "http://www.verisign.com"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\VeriSign
LDAP Search Return = "64"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\VeriSign
LDAP Timeout = "3c"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\VeriSign
LDAP Authentication = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\VeriSign
LDAP Search Base = "NULL"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\VeriSign
LDAP Simple Search = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\VeriSign
LDAP Logo = {random hex values}

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\WhoWhere
LDAP Server ID = "3"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\WhoWhere
Account Name = "WhoWhere Internet Directory Service"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\VeriSign
LDAP Server = "ldap.whowhere.com"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\VeriSign
LDAP URL = "http://www.whowhere.com"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\VeriSign
LDAP Search Return = "64"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\VeriSign
LDAP Timeout = "3c"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\VeriSign
LDAP Authentication = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\VeriSign
LDAP Simple Search = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts\VeriSign
LDAP Logo = {random hex values}

It creates the following registry entry(ies) to bypass Windows Firewall:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%Windows%\explorer.exe = "%Windows%\explorer.exe:*:Enabled:Windows Explorer"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\GloballyOpenPorts\
List
{random port number}:UDP = "{random port number}:UDP:*:Enabled:UDP {random port number}"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\GloballyOpenPorts\
List
{random port number}:TCP = "random port number}:TCP:*:Enabled:TCP {random port number}"

NOTES:

This spyware attempts to connect to the possibly malicious IP address {BLOCKED}.{BLOCKED}.135.107.

  SOLUTION

Minimum Scan Engine:

9.300

FIRST VSAPI PATTERN FILE:

10.286.02

FIRST VSAPI PATTERN DATE:

17 Sep 2013

VSAPI OPR PATTERN File:

10.287.00

VSAPI OPR PATTERN Date:

18 Sep 2013

Step 1

Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.

Step 2

Restart in Safe Mode

[ Learn More ]

Step 3

Delete this registry value

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • {random value} = "{%Application Data%\{random folder name}\{random file name}.exe"
  • In HKEY_CURRENT_USER\Software\Microsoft\WAB\WAB4\Wab File Name
    • (Default) = "%Application Data%\Microsoft\Address Book\{Username}.wab"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List
    • %Windows%\explorer.exe = "%Windows%\explorer.exe:*:Enabled:Windows Explorer"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\GloballyOpenPorts\List
    • 9224:UDP = "9224:UDP:*:Enabled:UDP 9224"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\GloballyOpenPorts\List
    • 2202:UDP = "2202:UDP:*:Enabled:UDP 2202"

Step 4

Delete this registry key

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Account Manager
    • HKEY_CURRENT_USER\Software\Microsoft\Internet Account Manager\Accounts
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Account Manager\Accounts\Active Directory GC
    • HKEY_CURRENT_USER\Software\Microsoft\Internet Account Manager\Accounts\VeriSign
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Account Manager\Accounts\Bigfoot
    • HKEY_CURRENT_USER\Software\Microsoft\Internet Account Manager\Accounts\WhoWhere

Step 5

Restart in normal mode and scan your computer with your Trend Micro product for files detected as TSPY_ZBOT.ULJ. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.

Step 6

The following created registry key(s) cannot be identified by the user since there are no reference values in the created key. The only way it can be identified is by comparing the present keys with a backup of the system registry. Note that the said key(s) do not have to be deleted since it won't be harmful to the system:

  • In HKEY_CURRENT_USER\Software\Microsoft
    • {random key value}


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