TSPY_GAMKER.NIL
Windows 2000, Windows XP, Windows Server 2003

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
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 Profile%\Application Data\zilesu.exe
(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.)
Autostart Technique
This spyware modifies the following registry entries to ensure it automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Winlogon
userinit = "%System%\userinit.exe,%User Profile%\APPLIC~1\zil,"
(Note: The default value data of the said registry entry is %Windows%\system32\userinit.exe,.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Winlogon
userinit = "%System%\userinit.exe,%User Profile%\APPLIC~1\zilesu.exe,"
(Note: The default value data of the said registry entry is %Windows%\system32\userinit.exe,.)
It registers as a system service to ensure its automatic execution at every system startup by adding the following registry keys:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\bulbashy
Other System Modifications
This spyware deletes the following files:
- %User Temp%\3.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 keys:
HKEY_LOCAL_MACHINE\software\microsoft\
help
It adds the following registry entries:
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\bulbashy
DisplayName = "Vba32 Armour Driver"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\bulbashy
ImagePath = "\??\%System%\drivers\bulbashy.sys"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\bulbashy
ErrorControl = "1"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\bulbashy
Start = "3"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\bulbashy
Type = "1"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
help
68AD0FD0 = "{random values}"
Dropping Routine
This spyware drops the following files:
- %System%\drivers\bulbashy.sys
- %Windows%\Tasks\nVidiaAgent.job
(Note: %System% is the Windows system folder, which is usually C:\Windows\System32.. %Windows% is the Windows folder, which is usually C:\Windows.)
This report is generated via an automated analysis system.
SOLUTION
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
Identify and delete files detected as TSPY_GAMKER.NIL using either the Startup Disk or Recovery Console
Step 3
Delete this registry key
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\SYSTEM\CurrentControlSet\Services
- bulbashy
- In HKEY_LOCAL_MACHINE\software\microsoft
- help
Step 4
Delete this registry value
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\SYSTEM\ControlSet001\Services\bulbashy
- DisplayName = "Vba32 Armour Driver"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\bulbashy
- ImagePath = "\??\%System%\drivers\bulbashy.sys"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\bulbashy
- ErrorControl = "1"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\bulbashy
- Start = "3"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\bulbashy
- Type = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\help
- 68AD0FD0 = "{random values}"
Step 5
Restore these modified registry values
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\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
- From: userinit = "%System%\userinit.exe,%User Profile%\APPLIC~1\zil,"
To: userinit = ""%Windows%\system32\userinit.exe,""
- From: userinit = "%System%\userinit.exe,%User Profile%\APPLIC~1\zil,"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
- From: userinit = "%System%\userinit.exe,%User Profile%\APPLIC~1\zilesu.exe,"
To: userinit = ""%Windows%\system32\userinit.exe,""
- From: userinit = "%System%\userinit.exe,%User Profile%\APPLIC~1\zilesu.exe,"
Step 6
Search and delete these components
- %System%\drivers\bulbashy.sys
- %Windows%\Tasks\nVidiaAgent.job
Step 7
Scan your computer with your Trend Micro product to delete files detected as TSPY_GAMKER.NIL. 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 8
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%\3.tmp
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