ALIASES:

PWS:Win32/Zbot (Microsoft); Trojan.Zbot (Symantec); Trojan-Spy.Win32.Zbot.bopd (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Trojan horse PSW.Generic10.ASLH (AVG)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

 OVERALL RISK RATING:
 REPORTED INFECTION:
 SYSTEM IMPACT RATING:
 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: 1,405,020 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 22 Apr 2013

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 creates the following folders:

  • %System Root%\DOCUME~1
  • %System Root%\DOCUME~1\ADMINI~1
  • %User Profile%\LOCALS~1

(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.. %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.)

Other System Modifications

This spyware deletes the following files:

  • %User Temp%\nst1.tmp

(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 and 7.)

It adds the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
MountPoints2\{4935142c-12c5-11e0-b495-806d6172696f}
BaseClass = "Drive"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
MountPoints2\{4935142e-12c5-11e0-b495-806d6172696f}
BaseClass = "Drive"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\ShellNoRoam\MUICache
%Desktop%\bot.exe = "bot"

It modifies the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Shell Folders
Personal = "%User Profile%\My Documents"

(Note: The default value data of the said registry entry is %User Profile%\My Documents.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
MountPoints2\D
BaseClass = "Drive"

(Note: The default value data of the said registry entry is Drive.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Shell Folders
Common Documents = "%User Profile%\Documents"

(Note: The default value data of the said registry entry is %System Root%\Documents and Settings\All Users\Documents.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Shell Folders
Desktop = "%Desktop%"

(Note: The default value data of the said registry entry is %User Profile%\Desktop.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
ZoneMap
ProxyBypass = "1"

(Note: The default value data of the said registry entry is 1.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
ZoneMap
IntranetName = "1"

(Note: The default value data of the said registry entry is 1.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
ZoneMap
UNCAsIntranet = "1"

(Note: The default value data of the said registry entry is 1.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Shell Folders
Cache = "%Temporary Internet Files%"

(Note: The default value data of the said registry entry is %User Profile%\Local Settings\Temporary Internet Files.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Shell Folders
Cookies = "%User Profile%\Cookies"

(Note: The default value data of the said registry entry is %User Profile%\Cookies.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Cache\Paths
Directory = "%Temporary Internet Files%\Content.IE5"

(Note: The default value data of the said registry entry is %User Profile%\Local Settings\Temporary Internet Files\Content.IE5.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Cache\Paths
Paths = "4"

(Note: The default value data of the said registry entry is 4.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Cache\Paths\path1
CachePath = "%Temporary Internet Files%\Content.IE5\Cache1"

(Note: The default value data of the said registry entry is %User Profile%\Local Settings\Temporary Internet Files\Content.IE5\Cache1.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Cache\Paths\path2
CachePath = "%Temporary Internet Files%\Content.IE5\Cache2"

(Note: The default value data of the said registry entry is %User Profile%\Local Settings\Temporary Internet Files\Content.IE5\Cache2.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Cache\Paths\path3
CachePath = "%Temporary Internet Files%\Content.IE5\Cache3"

(Note: The default value data of the said registry entry is %User Profile%\Local Settings\Temporary Internet Files\Content.IE5\Cache3.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Cache\Paths\path4
CachePath = "%Temporary Internet Files%\Content.IE5\Cache4"

(Note: The default value data of the said registry entry is %User Profile%\Local Settings\Temporary Internet Files\Content.IE5\Cache4.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Cache\Paths\path1
CacheLimit = "13fa6"

(Note: The default value data of the said registry entry is ffac.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Cache\Paths\path2
CacheLimit = "13fa6"

(Note: The default value data of the said registry entry is ffac.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Cache\Paths\path3
CacheLimit = "13fa6"

(Note: The default value data of the said registry entry is ffac.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Cache\Paths\path4
CacheLimit = "13fa6"

(Note: The default value data of the said registry entry is ffac.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Shell Folders
History = "%User Profile%\Local Settings\History"

(Note: The default value data of the said registry entry is %User Profile%\Local Settings\History.)

Dropping Routine

This spyware drops the following files:

  • %User Temp%\Sampleorder1.exe
  • %Application Data%\Spoon
  • %Application Data%\Spoon\Sandbox
  • %Application Data%\Spoon\Sandbox\1.0.0.0
  • %Application Data%\Spoon\Sandbox\1.0.0.0\xsandbox.bin.__tmp__
  • %Application Data%\Spoon\Sandbox\1.0.0.0\local\stubexe\0xCF28318C611AD3E8\bot.exe.__tmp__

(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 and 7.. %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.)

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine: 9.300

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

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\Explorer\MountPoints2\{4935142c-12c5-11e0-b495-806d6172696f}
    • BaseClass = "Drive"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{4935142e-12c5-11e0-b495-806d6172696f}
    • BaseClass = "Drive"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\ShellNoRoam\MUICache
    • %Desktop%\bot.exe = "bot"

Step 3

Restore these modified registry values

[ Learn More ]

Important:Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this only if you know how to or you can seek your system administrator's help. You may also check out this Microsoft article first before modifying your computer's registry.

  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders
    • From: Personal = "%User Profile%\My Documents"
      To: Personal = ""%User Profile%\My Documents""
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\D
    • From: BaseClass = "Drive"
      To: BaseClass = ""Drive""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders
    • From: Common Documents = "%User Profile%\Documents"
      To: Common Documents = ""%System Root%\Documents and Settings\All Users\Documents""
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders
    • From: Desktop = "%Desktop%"
      To: Desktop = ""%User Profile%\Desktop""
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap
    • From: ProxyBypass = "1"
      To: ProxyBypass = ""1""
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap
    • From: IntranetName = "1"
      To: IntranetName = ""1""
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap
    • From: UNCAsIntranet = "1"
      To: UNCAsIntranet = ""1""
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders
    • From: Cache = "%Temporary Internet Files%"
      To: Cache = ""%User Profile%\Local Settings\Temporary Internet Files""
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders
    • From: Cookies = "%User Profile%\Cookies"
      To: Cookies = ""%User Profile%\Cookies""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths
    • From: Directory = "%Temporary Internet Files%\Content.IE5"
      To: Directory = ""%User Profile%\Local Settings\Temporary Internet Files\Content.IE5""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths
    • From: Paths = "4"
      To: Paths = ""4""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path1
    • From: CachePath = "%Temporary Internet Files%\Content.IE5\Cache1"
      To: CachePath = ""%User Profile%\Local Settings\Temporary Internet Files\Content.IE5\Cache1""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path2
    • From: CachePath = "%Temporary Internet Files%\Content.IE5\Cache2"
      To: CachePath = ""%User Profile%\Local Settings\Temporary Internet Files\Content.IE5\Cache2""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path3
    • From: CachePath = "%Temporary Internet Files%\Content.IE5\Cache3"
      To: CachePath = ""%User Profile%\Local Settings\Temporary Internet Files\Content.IE5\Cache3""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path4
    • From: CachePath = "%Temporary Internet Files%\Content.IE5\Cache4"
      To: CachePath = ""%User Profile%\Local Settings\Temporary Internet Files\Content.IE5\Cache4""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path1
    • From: CacheLimit = "13fa6"
      To: CacheLimit = ""ffac""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path2
    • From: CacheLimit = "13fa6"
      To: CacheLimit = ""ffac""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path3
    • From: CacheLimit = "13fa6"
      To: CacheLimit = ""ffac""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path4
    • From: CacheLimit = "13fa6"
      To: CacheLimit = ""ffac""
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders
    • From: History = "%User Profile%\Local Settings\History"
      To: History = ""%User Profile%\Local Settings\History""

Step 4

Search and delete these components

[ Learn More ]
There may be some components 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.
  • %User Temp%\Sampleorder1.exe
  • %Application Data%\Spoon
  • %Application Data%\Spoon\Sandbox
  • %Application Data%\Spoon\Sandbox\1.0.0.0
  • %Application Data%\Spoon\Sandbox\1.0.0.0\xsandbox.bin.__tmp__
  • %Application Data%\Spoon\Sandbox\1.0.0.0\local\stubexe\0xCF28318C611AD3E8\bot.exe.__tmp__

Step 5

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.
  • %System Root%\DOCUME~1
  • %System Root%\DOCUME~1\ADMINI~1
  • %User Profile%\LOCALS~1

Step 6

Scan your computer with your Trend Micro product to delete files detected as TSPY_ZBOT.OMU. 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 7

Restore this file from backup only Microsoft-related files will be restored. If this malware/grayware also deleted files related to programs that are not from Microsoft, please reinstall those programs on you computer again.

  • %User Temp%\nst1.tmp


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