TSPY_CHISBURG.BO

February 08, 2014
 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:

2,995,712 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

08 Feb 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 copies of itself into the affected system:

  • %User Temp%\Win Update\Win Update.exe

(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 creates the following folders:

  • %User Temp%\Win Update
  • %User Temp%\Security
  • %User Temp%\Window Update
  • %User Profile%\Microsoft\Backups
  • %User Temp%\Windows Updates

(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.. %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.)

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
Win Update = "%User Temp%\Win Update\Win Update.exe"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Security = "%User Temp%\Security\Security.exe"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Window Update = "%User Temp%\Window Update\Window Update.exe"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Windows Updates = "%User Temp%\Windows Updates\Windows Updates.exe"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
System = "%User Temp%\loa.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
System = "%User Temp%\loa.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\828e61d4-90ca-43e6-896f-0fc0c1215dba
stubpath = "%User Temp%\loa.exe"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
System = "%User Profile%\Application Data\loa.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
System = "%User Profile%\Application Data\loa.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\dde41878-be7c-4ce6-8b4c-348272989387
stubpath = "%User Profile%\Application Data\loa.exe"

Other System Modifications

This spyware modifies the following file(s):

  • %User Profile%\Application Data\Microsoft

(Note: %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.)

It deletes the following files:

  • {malware path and file name}:zone.identifier
  • %User Temp%\se.exe:Zone.Identifier
  • %User Temp%\monn.exe:Zone.Identifier
  • %User Startup%\monn.exe:Zone.Identifier
  • %User Temp%\logmail.txt
  • %User Temp%\mo.exe:Zone.Identifier
  • %Windows%\Microsoft.NET\Framework\v2.0.50727\config\security.config.cch.1160.61921
  • %Windows%\Microsoft.NET\Framework\v2.0.50727\config\enterprisesec.config.cch.1160.61921
  • %User Profile%\v2.0.50727.42\security.config.cch.1160.62718
  • %User Temp%\uP6n4AERHH.ini
  • %User Temp%\4gXsKxqihU.ini

(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.. %User Startup% is the current user's Startup folder, which is usually C:\Windows\Profiles\{user name}\Start Menu\Programs\Startup on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Start Menu\Programs\Startup on Windows NT, and C:\Documents and Settings\{User name}\Start Menu\Programs\Startup.. %Windows% is the Windows folder, which is usually C:\Windows.. %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.)

It adds the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
ESENT\Process\mo

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
ESENT\Process\mo\
DEBUG

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\828e61d4-90ca-43e6-896f-0fc0c1215dba

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\dde41878-be7c-4ce6-8b4c-348272989387

It modifies the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Eventlog\Application\
ESENT
EventMessageFile = "%System%\ESENT.dll"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Eventlog\Application\
ESENT
CategoryMessageFile = "%System%\ESENT.dll"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Eventlog\Application\
ESENT
CategoryCount = "1"

(Note: The default value data of the said registry entry is 10.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Eventlog\Application\
ESENT
TypesSupported = "7"

(Note: The default value data of the said registry entry is 7.)

Dropping Routine

This spyware drops the following files:

  • %User Temp%\se.exe
  • %User Temp%\monn.exe
  • %User Temp%\mo.exe
  • %User Temp%\loa.exe
  • %User Profile%\Microsoft\Crypto
  • %User Profile%\Crypto\RSA
  • %User Profile%\RSA\S-1-5-21-1645522239-1292428093-682003330-1003
  • %User Profile%\Application Data\pid.txt
  • %User Profile%\Application Data\pidloc.txt
  • %User Temp%\logff.txt
  • %User Temp%\Security\Security.exe
  • %User Temp%\Window Update\Window Update.exe
  • %User Temp%\Windows Updates\Windows Updates.exe
  • %User Startup%\monn.exe

(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.. %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.. %User Startup% is the current user's Startup folder, which is usually C:\Windows\Profiles\{user name}\Start Menu\Programs\Startup on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Start Menu\Programs\Startup on Windows NT, and C:\Documents and Settings\{User name}\Start Menu\Programs\Startup.)

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

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_LOCAL_MACHINE\SOFTWARE\Microsoft\ESENT\Process
    • mo
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\ESENT\Process\mo
    • DEBUG
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Active Setup\Installed Components
    • 828e61d4-90ca-43e6-896f-0fc0c1215dba
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Active Setup\Installed Components
    • dde41878-be7c-4ce6-8b4c-348272989387

Step 4

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
    • Win Update = "%User Temp%\Win Update\Win Update.exe"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • Security = "%User Temp%\Security\Security.exe"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • Window Update = "%User Temp%\Window Update\Window Update.exe"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • Windows Updates = "%User Temp%\Windows Updates\Windows Updates.exe"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • System = "%User Temp%\loa.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    • System = "%User Temp%\loa.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Active Setup\Installed Components\828e61d4-90ca-43e6-896f-0fc0c1215dba
    • stubpath = "%User Temp%\loa.exe"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • System = "%User Profile%\Application Data\loa.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    • System = "%User Profile%\Application Data\loa.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Active Setup\Installed Components\dde41878-be7c-4ce6-8b4c-348272989387
    • stubpath = "%User Profile%\Application Data\loa.exe"

Step 5

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_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Eventlog\Application\ESENT
    • From: EventMessageFile = "%System%\ESENT.dll"
      To: EventMessageFile = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Eventlog\Application\ESENT
    • From: CategoryMessageFile = "%System%\ESENT.dll"
      To: CategoryMessageFile = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Eventlog\Application\ESENT
    • From: CategoryCount = "1"
      To: CategoryCount = ""10""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Eventlog\Application\ESENT
    • From: TypesSupported = "7"
      To: TypesSupported = ""7""

Step 6

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%\se.exe
  • %User Temp%\monn.exe
  • %User Temp%\mo.exe
  • %User Temp%\loa.exe
  • %User Profile%\Microsoft\Crypto
  • %User Profile%\Crypto\RSA
  • %User Profile%\RSA\S-1-5-21-1645522239-1292428093-682003330-1003
  • %User Profile%\Application Data\pid.txt
  • %User Profile%\Application Data\pidloc.txt
  • %User Temp%\logff.txt
  • %User Temp%\Security\Security.exe
  • %User Temp%\Window Update\Window Update.exe
  • %User Temp%\Windows Updates\Windows Updates.exe
  • %User Startup%\monn.exe

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.
  • %User Temp%\Win Update
  • %User Temp%\Security
  • %User Temp%\Window Update
  • %User Profile%\Microsoft\Backups
  • %User Temp%\Windows Updates

Step 8

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

Restore deleted/modified files and/or registry entries from backup

*Note: Only Microsoft-related files/keys/values will be restored. If this malware/grayware also deleted registry keys/values related to programs that are not from Microsoft, please reinstall those programs on your computer.

    • %User Profile%\Application Data\Microsoft

Step 10

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.

  • {malware path and file name}:zone.identifier
  • %User Temp%\se.exe:Zone.Identifier
  • %User Temp%\monn.exe:Zone.Identifier
  • %User Startup%\monn.exe:Zone.Identifier
  • %User Temp%\logmail.txt
  • %User Temp%\mo.exe:Zone.Identifier
  • %Windows%\Microsoft.NET\Framework\v2.0.50727\config\security.config.cch.1160.61921
  • %Windows%\Microsoft.NET\Framework\v2.0.50727\config\enterprisesec.config.cch.1160.61921
  • %User Profile%\v2.0.50727.42\security.config.cch.1160.62718
  • %User Temp%\uP6n4AERHH.ini
  • %User Temp%\4gXsKxqihU.ini


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