TROJ_FAKESYSD.JQ
Windows 2000, Windows XP, Windows Server 2003
Threat Type: Trojan
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
It adds certain registry entries to disable the Task Manager. This action prevents users from terminating the malware process, which can usually be done via the Task Manager.
It deletes the initially executed copy of itself.
TECHNICAL DETAILS
Arrival Details
This Trojan 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 Trojan drops the following copies of itself into the affected system:
- %System Root%\Documents and Settings\All Users\Application Data\{random filename}.exe
(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)
It creates the following folders:
- %User Temp%\smtmp
- %User Temp%\smtmp\1
- %User Temp%\smtmp\2
- %User Temp%\smtmp\3
- %User Temp%\smtmp\4
(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.)
Autostart Technique
This Trojan adds the following registry entries to enable its automatic execution at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{random file name} = "%System Root%\Documents and Settings\All Users\Application Data\{random file name}.exe"
Other System Modifications
This Trojan adds the following registry entries as part of its installation routine:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
Explorer
NoDesktop = "1"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
ActiveDesktop
NoChangingWallPaper = "1"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
Attachments
SaveZoneInformation = "1"
It adds the following registry entries to disable the Task Manager:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
System
DisableTaskMgr = "1"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
system
DisableTaskMgr = "1"
It modifies the following registry entries to hide files with Hidden attributes:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
Hidden = "0"
(Note: The default value data of the said registry entry is 1.)
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
ShowSuperHidden = "0"
(Note: The default value data of the said registry entry is 1.)
Other Details
This Trojan deletes the initially executed copy of itself
NOTES:
This malware moves specific files in the following directories:
Operating System major version is 5 (XP, 2000, 2003):
From: %System Root%\Documents and Settings\All Users\Start Menu\
To: %User Temp%\smtmp\1\
From: %User Profile%\Application Data\Microsoft\Internet Explorer\Quick Launch\
To: %User Temp%\smtmp\2\
From: %System Root%\Documents and Settings\All Users\Desktop\
To: %User Temp%\smtmp\4\
Operating System major version is 6 (Vista, 2008, 7)
From: %System Root%\ProgramData\Start Menu\
To: %User Temp%\smtmp\1\
From: %User Profile%\Application Data\Roaming\Microsoft\Internet Explorer\Quick Launch\
To: %User Temp%\smtmp\2\
From: %User Profile%\Application Data\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\TaskBar\
To: %User Temp%\smtmp\3\
From: %System Root%\ProgramData\Desktop\
To: %User Temp%\smtmp\4\
It also modifies the attributes of files found in the affected system into Hidden, to trick the users that the files have been deleted.
SOLUTION
Step 1
For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.
Step 2
Identify and terminate files detected as TROJ_FAKESYSD.JQ
- If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
- If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.
Step 3
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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- {random file name} = "%System Root%\Documents and Settings\All Users\Application Data\{random file name}.exe"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\System
- DisableTaskMgr = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\system
- DisableTaskMgr = "1"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer
- NoDesktop = "1"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\ActiveDesktop
- NoChangingWallPaper = "1"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Attachments
- SaveZoneInformation = "1"
Step 4
Restore this modified 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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
- From: Hidden = "0"
- To: Hidden = "1"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
- From: ShowSuperHidden = "0"
- To: ShowSuperHidden = "1"
Step 5
Scan your computer with your Trend Micro product to delete files detected as TROJ_FAKESYSD.JQ. 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.
NOTES:
RECOMMENDATIONS
To unhide the files hidden by this malware, perform the following steps:
1. Open a Command Prompt.
For Windows 2000, Windows XP, and Windows Server 2003 users:
Click Start > Run, type CMD in the text box provided, and then press Enter.
For Windows Vista and Windows 7 users:
Click the Start button, type CMD in the Search input field then press Enter.
2. For every drive in the computer, type the following command:
attrib -h {drive letter}:\*.* /s /d
3. Close Command Prompt. Type exit then press Enter.
To Restore Files to its Original Location:
Open %User Temp%\smtmp and copy the files as follows:
If operating system major version is 5 (XP, 2000, 2003):
From: %User Temp%\smtmp\1\
To: %System Root%\Documents and Settings\All Users\Start Menu\
From: %User Temp%\smtmp\2\
To: %User Profile%\Application Data\Microsoft\Internet Explorer\Quick
Launch\ From: %User Temp%\smtmp\4\
To: %System Root%\Documents and Settings\All Users\Desktop\
If operating system major version is 6 (Vista, 2008, 7)
From: %User Temp%\smtmp\1\
To: %System Root%\ProgramData\Start Menu\
From: %User Temp%\smtmp\2\
To: %User Profile%\Application Data\Roaming\Microsoft\Internet Explorer\Quick Launch\
From: %User Temp%\smtmp\3\
To: %User Profile%\Application Data\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\TaskBar\
From: %User Temp%\smtmp\4\
To: %System Root%\ProgramData\Desktop\
After moving the files, delete the folder %User Temp%\smtmp.
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