TSPY_ZBOT.YYDJZ

 Modified by: Jaime Benigno Reyes

 ALIASES:

PWS:Win32/Zbot (Microsoft); Trojan-Spy.Win32.Zbot.ulan (Kaspersky); PWSZbot-FADO!8465D44F70BC (McAfee)

 PLATFORM:

Windows

 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:

287,795 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

24 Oct 2014

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 files:

  • %Windows%\Tasks\Security Center Update - {number}.job

(Note: %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.)

It drops the following copies of itself into the affected system:

  • %Application Data%\{random folder}\{random name 1}.exe
  • %System%\{random name 2}.exe

(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.. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

It creates the following folders:

  • %Application Data%\{random folder}

(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.)

Autostart Technique

This spyware registers itself as a system service to ensure its automatic execution at every system startup by adding the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SecurityCenterServer{number}
ImagePath = "%System%\{random name 2}.exe -service %Application Data%\{random folder}\{random name 1}.exe"

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{random entry} = "%Application Data%\{random folder}\{random name 1}.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
{random entry} = "%Application Data%\{random folder}\{random name 1}.exe"

Other System Modifications

This spyware adds the following registry keys:

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main\FeatureControl

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main\FeatureControl\
FEATURE_BROWSER_EMULATION

HKEY_CURRENT_USER\Software\{random key 1}

HKEY_CURRENT_USER\Software\{random key 2}

HKEY_LOCAL_MACHINE\SOFTWARE\{random key 1}

HKEY_LOCAL_MACHINE\SOFTWARE\{random key 2}

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SecurityCenterServer{number}

It adds the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\BrowserEmulation
IECompatVersionHigh = "524288"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\BrowserEmulation
IECompatVersionLow = "498089985

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\BrowserEmulation
StaleCompatCache = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main\FeatureControl\
FEATURE_BROWSER_EMULATION
{random name 1}.exe = "11001"

HKEY_CURRENT_USER\Software\{random key 1}
License = "444"

HKEY_LOCAL_MACHINE\SOFTWARE\{random key 1}
License = "444"

Other Details

This spyware connects to the following possibly malicious URL:

  • http://{BLOCKED}uice.su/b/opt/{hash}
  • http://{BLOCKED}ance.su/b/eve/{hash}
  • http://{BLOCKED}ance.su/b/opt/{hash}
  • http://{BLOCKED}efox.su/b/opt/{hash}

  SOLUTION

Minimum Scan Engine:

9.700

FIRST VSAPI PATTERN FILE:

11.232.01

FIRST VSAPI PATTERN DATE:

24 Oct 2014

VSAPI OPR PATTERN File:

11.233.00

VSAPI OPR PATTERN Date:

25 Oct 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

Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.

Step 3

Restart in Safe Mode

[ Learn More ]

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 Explorer\Main
    • FeatureControl
  • In HKEY_CURRENT_USER\Software
    • {random key 1}
  • In HKEY_CURRENT_USER\Software
    • {random key 2}
  • In HKEY_LOCAL_MACHINE\SOFTWARE
    • {random key 1}
  • In HKEY_LOCAL_MACHINE\SOFTWARE
    • {random key 2}
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
    • SecurityCenterServer{number}

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 entry} = "%Application Data%\{random folder}\{random name 1}.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    • {random entry} = "%Application Data%\{random folder}\{random name 1}.exe"
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\BrowserEmulation
    • IECompatVersionHigh = "524288"
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\BrowserEmulation
    • IECompatVersionLow = "498089985
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\BrowserEmulation
    • StaleCompatCache = "1"

Step 6

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%\{random folder}

Step 7

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.
  • %Windows%\Tasks\Security Center Update - {number}.job

Step 8

Restart in normal mode and scan your computer with your Trend Micro product for files detected as TSPY_ZBOT.YYDJZ. 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 9

The following created files/folders/registry keys/registry entries 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 system information with a backup. Note that the said components do not have to be deleted since it won't be harmful to the system.

  • HKEY_CURRENT_USER\Software\{random key 1}
  • HKEY_CURRENT_USER\Software\{random key 2}
  • HKEY_LOCAL_MACHINE\SOFTWARE\{random key 1}
  • HKEY_LOCAL_MACHINE\SOFTWARE\{random key 2}


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