TROJ_FAKEAV.MCJ
UltraDefragFraud!gen1 (Symantec)
Windows 2000, Windows XP, Windows Server 2003

Threat Type: Trojan
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
This Trojan may be dropped by other malware. It may be unknowingly downloaded by a user while visiting malicious websites.
It lowers the security setting of Internet Explorer.
It deletes the initially executed copy of itself.
TECHNICAL DETAILS
410,624 bytes
EXE
Yes
16 Jun 2011
Arrival Details
This Trojan may be dropped by other malware.
It may be unknowingly downloaded by a user while visiting malicious websites.
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 drops the following files:
- %System Root%\Documents and Settings\All Users\Application Data\{random filename}
(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:
- %Start Menu%\Programs\{OS Name} Restore
(Note: %Start Menu% is the current user's Start Menu folder, which is usually C:\Windows\Profiles\{user name}\Start Menu on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Start Menu on Windows NT and C:\Windows\Start Menu or C:\Documents and Settings\{User name}\Start Menu on Windows 2000, XP, and Server 2003.)
Other System Modifications
This Trojan adds the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
Use FormSuggest = "Yes"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings
WarnOnZoneCrossing = "0"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings
WarnonBadCertRecving = "0"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings
CertificateRevocation = "0"
Web Browser Home Page and Search Page Modification
This Trojan lowers the security setting of Internet Explorer.
Dropping Routine
This Trojan drops the following files:
- %Desktop%\{OS Name} Restore.lnk
- %Start Menu%\Programs\{OS Name} Restore\{OS Name} Restore.lnk
- %Start Menu%\Programs\{OS Name} Restore\Uninstall {OS Name} Restore.lnk
(Note: %Desktop% is the current user's desktop, which is usually C:\Windows\Profiles\{user name}\Desktop on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Desktop on Windows NT, and C:\Documents and Settings\{User Name}\Desktop on Windows 2000, XP, and Server 2003.. %Start Menu% is the current user's Start Menu folder, which is usually C:\Windows\Profiles\{user name}\Start Menu on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Start Menu on Windows NT and C:\Windows\Start Menu or C:\Documents and Settings\{User name}\Start Menu on Windows 2000, XP, and Server 2003.)
Other Details
This Trojan deletes the initially executed copy of itself
SOLUTION
8.900
8.228.10
16 Jun 2011
8.229.00
17 Jun 2011
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_FAKEAV.MCJ
- 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\Internet Explorer\Main
- Use FormSuggest = "Yes"
- Use FormSuggest = "Yes"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings
- WarnOnZoneCrossing = "0"
- WarnOnZoneCrossing = "0"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings
- WarnonBadCertRecving = "0"
- WarnonBadCertRecving = "0"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings
- CertificateRevocation = "0"
- CertificateRevocation = "0"
Step 4
Reset Internet security settings
Step 5
Search and delete these files
- %System Root%\Documents and Settings\All Users\Application Data\{random file name}
- %Desktop%\{OS Name} Restore.lnk
Step 6
Search and delete this folder
- %Start Menu%\Programs\{OS Name} Restore
Step 7
Scan your computer with your Trend Micro product to delete files detected as TROJ_FAKEAV.MCJ. 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.
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