TSPY_ZBOT.KVV


 ALIASES:

Win32/Spy.Zbot.AAO (Eset), Trojan-PWS.Win32.Fareit/Backdoor.Word.DarkKomet (Ikarus), Backdoor.Win32.DarkKomet.byft (Kaspersky), Mal/Necurs-I (Sophos)

 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: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Dropped by other malware, Downloaded from the Internet, Spammed via email

This spyware arrives as an attachment to email messages spammed by other malware/grayware or malicious users. It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites. It may be dropped by other malware.

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

It modifies the Internet Explorer Zone Settings.

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

  TECHNICAL DETAILS

File Size:

276,629 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

30 Jan 2014

Payload:

Downloads files

Arrival Details

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

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

It may be dropped by the following malware:

  • an RTF file also detected as TSPY_ZBOT.KVV

Installation

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

  • %Application Data%\Quittung 2014-21-01.exe - dropped by the RTF file detected as TSPY_ZBOT.KVV
  • %Application Data%\{random1}\{random}.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.)

It drops the following files:

  • %Application Data%\{random2}\{random}.{random}
  • %Application Data%\Microsoft\Address Book\{OS version}.wab
  • %Application Data%\Microsoft\Address Book\{user name}.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.)

It creates the following folders:

  • %Application Data%\{random1}
  • %Application Data%\{random2}
  • %Application Data%\Microsoft\Address Book

(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.)

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

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} = "%Application Data%\{random1}\{random}.exe"

Other System Modifications

This spyware adds the following registry keys:

HKEY_CURRENT_USER\Software\Microsoft\
{random}

HKEY_CURRENT_USER\Software\Microsoft\
WAB

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
{port}:UDP = "{port}:UDP:Enabled:UDP {port}"

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

Web Browser Home Page and Search Page Modification

This spyware modifies the Internet Explorer Zone Settings.

Information Theft

This spyware accesses the following site to download its configuration file:

  • http://{BLOCKED}ski.prfact.ch/sadcxvbv/vdfbffddf.php|file=config2.bin

Stolen Information

This spyware sends the gathered information via HTTP POST to the following URL:

  • http://{BLOCKED}ec948fa2bc.com/53085816/0d5e28f7.php

Other Details

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

It deletes the initially executed copy of itself

NOTES:

This malware is an embedded .EXE file to a .RTF file that is disguised as an image:

The users are tricked into double-clicking the fake image above and as a result, the copy of TSPY_ZBOT.KVV(.EXE file) is dropped on the system.

The configuration file may contain URLs where it downloads an updated copy of itself and sends its gathered information. It may also contain URLs of its target online banking and finance-related sites from where it steals information.

It may also gather the following information from the affected system:

  • 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
  • FTP credentials
  • Online banking credentials
  • Flashplayer data
  • Personal digital cerificates

  SOLUTION

Minimum Scan Engine:

9.700

FIRST VSAPI PATTERN FILE:

10.574.05

FIRST VSAPI PATTERN DATE:

30 Jan 2014

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 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
    • WAB

Step 4

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:

HKEY_CURRENT_USER\Software\Microsoft\{random}

Step 5

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} = "%Application Data%\{random1}\{random}.exe"
  • 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
    • {port}:UDP = "{port}:UDP:Enabled:UDP {port}"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\GloballyOpenPorts\List
    • {port}:TCP = "{port}:TCP:Enabled:TCP {port}"

Step 6

Reset Internet security settings

[ Learn More ]

Step 7

Search and delete these folders

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
  • %Application Data%\{random1}
  • %Application Data%\{random2}
  • %Application Data%\Microsoft\Address Book

Step 8

Search and delete this file

[ Learn More ]
There may be some files that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the "More advanced options" option to include all hidden files and folders in the search result.
  • %Application Data%\Microsoft\Address Book\{OS version}.wab
  • %Application Data%\Microsoft\Address Book\{OS version}.wab~

Step 9

Restart in normal mode and scan your computer with your Trend Micro product for files detected as TSPY_ZBOT.KVV. 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.


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