ADW_LOOTS
Windows 2000, Windows XP, Windows Server 2003
Threat Type: Adware
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
This adware arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
It deletes itself after execution.
TECHNICAL DETAILS
Arrival Details
This adware 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 adware creates the following folders:
- %System Root%\DOCUME~1
- %System Root%\DOCUME~1\Wilbert
- %User Profile%\LOCALS~1
- %User Temp%\nsc3.tmp
- %Program Files%\STool
(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.. %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.. %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000, Server 2003, and XP (32-bit), Vista (32-bit), and 7 (32-bit), or C:\Program Files (x86) in Windows XP (64-bit), Vista (64-bit), and 7 (64-bit).)
Autostart Technique
This adware adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
STool = "%Program Files%\STool\STool.exe"
It registers itself as a BHO to ensure its automatic execution every time Internet Explorer is used by adding the following registry keys:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Browser Helper Objects\{88B3E7BD-0AD1-44FD-823F-9E880D871D5D}
Other System Modifications
This adware deletes the following files:
- %User Temp%\nsm1.tmp
- %User Temp%\nsc3.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_CURRENT_USER\Software\STool
HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows\CurrentVersion\Uninstall\
STool
HKEY_CLASSES_ROOT\STool.SToolHelper.1
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
STool.SToolHelper.1\CLSID
HKEY_CLASSES_ROOT\STool.SToolHelper
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
STool.SToolHelper\CLSID
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
STool.SToolHelper\CurVer
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{88B3E7BD-0AD1-44FD-823F-9E880D871D5D}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{88B3E7BD-0AD1-44FD-823F-9E880D871D5D}\ProgID
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{88B3E7BD-0AD1-44FD-823F-9E880D871D5D}\VersionIndependentProgID
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{88B3E7BD-0AD1-44FD-823F-9E880D871D5D}\Programmable
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{88B3E7BD-0AD1-44FD-823F-9E880D871D5D}\InprocServer32
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{88B3E7BD-0AD1-44FD-823F-9E880D871D5D}\TypeLib
HKEY_CLASSES_ROOT\STool.SToolBand.1
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
STool.SToolBand.1\CLSID
HKEY_CLASSES_ROOT\STool.SToolBand
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
STool.SToolBand\CLSID
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
STool.SToolBand\CurVer
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{C5C4B8B0-6077-4E32-BC18-A45FB81BC6B4}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{C5C4B8B0-6077-4E32-BC18-A45FB81BC6B4}\ProgID
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{C5C4B8B0-6077-4E32-BC18-A45FB81BC6B4}\VersionIndependentProgID
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{C5C4B8B0-6077-4E32-BC18-A45FB81BC6B4}\Programmable
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{C5C4B8B0-6077-4E32-BC18-A45FB81BC6B4}\InprocServer32
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{C5C4B8B0-6077-4E32-BC18-A45FB81BC6B4}\TypeLib
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{DAE862B4-222D-416D-8A46-8BD200051081}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{DAE862B4-222D-416D-8A46-8BD200051081}\1.0
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{DAE862B4-222D-416D-8A46-8BD200051081}\1.0\
FLAGS
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{DAE862B4-222D-416D-8A46-8BD200051081}\1.0\
0
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{DAE862B4-222D-416D-8A46-8BD200051081}\1.0\
0\win32
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{DAE862B4-222D-416D-8A46-8BD200051081}\1.0\
HELPDIR
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{9637E77D-5B79-4331-9103-A6F3EAE6C57D}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{9637E77D-5B79-4331-9103-A6F3EAE6C57D}\ProxyStubClsid
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{9637E77D-5B79-4331-9103-A6F3EAE6C57D}\ProxyStubClsid32
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{9637E77D-5B79-4331-9103-A6F3EAE6C57D}\TypeLib
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{A6344D7D-596E-4E9B-9AFE-CCF1C04E2B6C}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{A6344D7D-596E-4E9B-9AFE-CCF1C04E2B6C}\ProxyStubClsid
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{A6344D7D-596E-4E9B-9AFE-CCF1C04E2B6C}\ProxyStubClsid32
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{A6344D7D-596E-4E9B-9AFE-CCF1C04E2B6C}\TypeLib
It adds the following registry entries:
HKEY_CURRENT_USER\Software\STool
id = "SD39"
HKEY_CURRENT_USER\Software\STool
version = "1.0.0.3"
HKEY_CURRENT_USER\Software\STool
inst = "{malware path and file name}"
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
TabProcGrowth = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Internet Explorer\Main
TabProcGrowth = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
STool
DisplayName = "STool"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
STool
UninstallString = "%Program Files%\STool\Uninstall.exe"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
STool
Publisher = "NBIZ"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
STool
NoModify = "1"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
STool
NoRepair = "1"
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{88B3E7BD-0AD1-44FD-823F-9E880D871D5D}\InprocServer32
ThreadingModel = "Apartment"
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{C5C4B8B0-6077-4E32-BC18-A45FB81BC6B4}\InprocServer32
ThreadingModel = "Apartment"
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{9637E77D-5B79-4331-9103-A6F3EAE6C57D}\TypeLib
Version = "1.0"
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{A6344D7D-596E-4E9B-9AFE-CCF1C04E2B6C}\TypeLib
Version = "1.0"
It deletes the following registry keys:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Discardable\PostSetup\Component Categories\
{00021493-0000-0000-C000-000000000046}\Enum
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Discardable\PostSetup\Component Categories\
{00021494-0000-0000-C000-000000000046}\Enum
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{C5C4B8B0-6077-4E32-BC18-A45FB81BC6B4}\Implemented Categories\
{00021493-0000-0000-C000-000000000046}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{C5C4B8B0-6077-4E32-BC18-A45FB81BC6B4}\Implemented Categories
Dropping Routine
This adware drops the following files:
- %User Temp%\nsc3.tmp\nsProcess.dll
- %User Temp%\nsc3.tmp\UAC.dll
- %Program Files%\STool\STool.dll
- %Program Files%\STool\STool.exe
- %User Temp%\nsc3.tmp\System.dll
- %Program Files%\STool\Uninstall.exe
- %User Temp%\nsc3.tmp\IpConfig.dll
- %User Temp%\nsc3.tmp\NSISdl.dll
- %User Temp%\inst.xxx
- %Program Files%\STool\setting.dat
(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.. %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000, Server 2003, and XP (32-bit), Vista (32-bit), and 7 (32-bit), or C:\Program Files (x86) in Windows XP (64-bit), Vista (64-bit), and 7 (64-bit).)
Other Details
This adware connects to the following possibly malicious URL:
- http://stool.{BLOCKED}o.co.kr/update/SD39/STool.ini
- http://www.{BLOCKED}o.co.kr/setting.dat
It deletes itself after execution.
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
Restart in Safe Mode
Step 3
Close all opened browser windows
Step 4
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_CURRENT_USER\Software
- STool
- In HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Uninstall
- STool
- In HKEY_CLASSES_ROOT
- STool.SToolHelper.1
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\STool.SToolHelper.1
- CLSID
- In HKEY_CLASSES_ROOT
- STool.SToolHelper
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\STool.SToolHelper
- CLSID
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\STool.SToolHelper
- CurVer
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID
- {88B3E7BD-0AD1-44FD-823F-9E880D871D5D}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{88B3E7BD-0AD1-44FD-823F-9E880D871D5D}
- ProgID
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{88B3E7BD-0AD1-44FD-823F-9E880D871D5D}
- VersionIndependentProgID
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{88B3E7BD-0AD1-44FD-823F-9E880D871D5D}
- Programmable
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{88B3E7BD-0AD1-44FD-823F-9E880D871D5D}
- InprocServer32
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{88B3E7BD-0AD1-44FD-823F-9E880D871D5D}
- TypeLib
- In HKEY_CLASSES_ROOT
- STool.SToolBand.1
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\STool.SToolBand.1
- CLSID
- In HKEY_CLASSES_ROOT
- STool.SToolBand
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\STool.SToolBand
- CLSID
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\STool.SToolBand
- CurVer
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID
- {C5C4B8B0-6077-4E32-BC18-A45FB81BC6B4}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{C5C4B8B0-6077-4E32-BC18-A45FB81BC6B4}
- ProgID
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{C5C4B8B0-6077-4E32-BC18-A45FB81BC6B4}
- VersionIndependentProgID
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{C5C4B8B0-6077-4E32-BC18-A45FB81BC6B4}
- Programmable
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{C5C4B8B0-6077-4E32-BC18-A45FB81BC6B4}
- InprocServer32
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{C5C4B8B0-6077-4E32-BC18-A45FB81BC6B4}
- TypeLib
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib
- {DAE862B4-222D-416D-8A46-8BD200051081}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib\{DAE862B4-222D-416D-8A46-8BD200051081}
- 1.0
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib\{DAE862B4-222D-416D-8A46-8BD200051081}\1.0
- FLAGS
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib\{DAE862B4-222D-416D-8A46-8BD200051081}\1.0
- 0
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib\{DAE862B4-222D-416D-8A46-8BD200051081}\1.0\0
- win32
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib\{DAE862B4-222D-416D-8A46-8BD200051081}\1.0
- HELPDIR
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface
- {9637E77D-5B79-4331-9103-A6F3EAE6C57D}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{9637E77D-5B79-4331-9103-A6F3EAE6C57D}
- ProxyStubClsid
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{9637E77D-5B79-4331-9103-A6F3EAE6C57D}
- ProxyStubClsid32
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{9637E77D-5B79-4331-9103-A6F3EAE6C57D}
- TypeLib
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface
- {A6344D7D-596E-4E9B-9AFE-CCF1C04E2B6C}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{A6344D7D-596E-4E9B-9AFE-CCF1C04E2B6C}
- ProxyStubClsid
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{A6344D7D-596E-4E9B-9AFE-CCF1C04E2B6C}
- ProxyStubClsid32
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{A6344D7D-596E-4E9B-9AFE-CCF1C04E2B6C}
- TypeLib
Step 5
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\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
- STool = "%Program Files%\STool\STool.exe"
- In HKEY_CURRENT_USER\Software\STool
- id = "SD39"
- In HKEY_CURRENT_USER\Software\STool
- version = "1.0.0.3"
- In HKEY_CURRENT_USER\Software\STool
- inst = "{malware path and file name}"
- In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main
- TabProcGrowth = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\Main
- TabProcGrowth = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\STool
- DisplayName = "STool"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\STool
- UninstallString = "%Program Files%\STool\Uninstall.exe"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\STool
- Publisher = "NBIZ"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\STool
- NoModify = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\STool
- NoRepair = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{88B3E7BD-0AD1-44FD-823F-9E880D871D5D}\InprocServer32
- ThreadingModel = "Apartment"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{C5C4B8B0-6077-4E32-BC18-A45FB81BC6B4}\InprocServer32
- ThreadingModel = "Apartment"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{9637E77D-5B79-4331-9103-A6F3EAE6C57D}\TypeLib
- Version = "1.0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{A6344D7D-596E-4E9B-9AFE-CCF1C04E2B6C}\TypeLib
- Version = "1.0"
Step 6
Search and delete these components
- %User Temp%\nsc3.tmp\nsProcess.dll
- %User Temp%\nsc3.tmp\UAC.dll
- %Program Files%\STool\STool.dll
- %Program Files%\STool\STool.exe
- %User Temp%\nsc3.tmp\System.dll
- %Program Files%\STool\Uninstall.exe
- %User Temp%\nsc3.tmp\IpConfig.dll
- %User Temp%\nsc3.tmp\NSISdl.dll
- %User Temp%\inst.xxx
- %Program Files%\STool\setting.dat
Step 7
Search and delete these folders
- %System Root%\DOCUME~1
- %System Root%\DOCUME~1\Wilbert
- %User Profile%\LOCALS~1
- %User Temp%\nsc3.tmp
- %Program Files%\STool
Step 8
Restart in normal mode and scan your computer with your Trend Micro product for files detected as ADW_LOOTS. 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 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%\nsm1.tmp
- %User Temp%\nsc3.tmp
Step 10
Restore these deleted registry keys/values from backup
*Note: Only Microsoft-related keys/values will be restored. If the malware/grayware also deleted registry keys/values related to programs that are not from Microsoft, please reinstall those programs on your computer.
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Discardable\PostSetup\Component Categories\{00021493-0000-0000-C000-000000000046}
- Enum
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Discardable\PostSetup\Component Categories\{00021494-0000-0000-C000-000000000046}
- Enum
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{C5C4B8B0-6077-4E32-BC18-A45FB81BC6B4}\Implemented Categories
- {00021493-0000-0000-C000-000000000046}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{C5C4B8B0-6077-4E32-BC18-A45FB81BC6B4}
- Implemented Categories
Did this description help? Tell us how we did.