WORM_UTOTI.MUL
Windows 2000, Windows XP, Windows Server 2003
Threat Type: Worm
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
This worm 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 worm 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 worm drops the following copies of itself into the affected system:
- %User Profile%\Application Data\lssass.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 worm adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
Microsoft = "%User Profile%\Application Data\lssass.exe"
Other System Modifications
This worm deletes the following files:
- %User Temp%\58e0ef.mst
- %User Temp%\AdobeARM.log
- %User Temp%\AdobeSFX.log
- %User Temp%\ASPNETSetup_00000.log
- %User Temp%\ASPNETSetup_00001.log
- %User Temp%\ASPNETSetup_00002.log
- %User Temp%\dd_depcheck_NETFX_EXP_35.txt
- %User Temp%\dd_dotnetfx35error.txt
- %User Temp%\dd_dotnetfx35install.txt
- %User Temp%\dd_dotNetFx40_Full_x86_x64_decompression_log.txt
- %User Temp%\dd_MSXML6_MSI0686.txt
- %User Temp%\dd_netfx20MSI7F16.txt
- %User Temp%\dd_netfx20UI7F16.txt
- %User Temp%\dd_NET_Framework20_Setup06A7.txt
- %User Temp%\dd_NET_Framework30_Setup0775.txt
- %User Temp%\dd_NET_Framework35_MSI07B9.txt
- %User Temp%\dd_RGB9RAST_x86.msi0683.txt
- %User Temp%\dd_vcredistMSI3CAA.txt
- %User Temp%\dd_vcredistMSI7C21.txt
- %User Temp%\dd_vcredistUI3CAA.txt
- %User Temp%\dd_vcredistUI7C21.txt
- %User Temp%\dd_wcf_CA_smci_20111017_044900_062.txt
- %User Temp%\dd_wcf_retCA29BA.txt
- %User Temp%\dd_WIC.txt
- %User Temp%\dd_XPS.txt
- %User Temp%\Microsoft .NET Framework 4 Setup_20111016_234618578-MSI_netfx_Core_x86.msi.txt
- %User Temp%\Microsoft .NET Framework 4 Setup_20111016_234618578-MSI_netfx_Extended_x86.msi.txt
- %User Temp%\Microsoft .NET Framework 4 Setup_20111016_234618578.html
- %User Temp%\Microsoft Visual C++ 2010 x86 Redistributable Setup_20111020_000954642-MSI_vc_red.msi.txt
- %User Temp%\Microsoft Visual C++ 2010 x86 Redistributable Setup_20111020_000954642.html
- %User Temp%\NonFound
- %User Profile%\Application Data\lssass.exe
- %User Temp%\{malware file name}32_d.exe
- %User Temp%\JX32_H.exe
- %User Temp%\NY32_O.exe
- %User Temp%\QZ32_V.exe
- %User Temp%\uxeventlog.txt
- %User Temp%\vminst.log_20111016_212239_Failed.log
- %User Temp%\vminst.log_20130313_012028.log
- %User Temp%\vminst.log_20130313_012352_Failed.log
- %User Temp%\vmmsi.log_20111016_212246_Failed.log
- %User Temp%\vmmsi.log_20130313_012028.log
- %User Temp%\vmmsi.log_20130313_012352_Failed.log
- %User Temp%\WSFF8.tmp
- %User Temp%\WSFF9.tmp
- %User Temp%\GG32_S.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.)
Dropping Routine
This worm drops the following files:
- %User Temp%\NY.exe
- %User Temp%\JX.exe
- %User Temp%\QZ.exe
- %User Temp%\WX.exe
- %User Temp%\YZ.exe
- %User Temp%\YJ.exe
- %User Temp%\GG.exe
- %User Temp%\YW.exe
- %User Temp%\WO.exe
- %User Temp%\GW.exe
- %User Temp%\HO.exe
- %User Profile%\Application Data\lssass.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.)
Other Details
This worm connects to the following possibly malicious URL:
- http://{BLOCKED}n.com/sxl
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
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
- Microsoft = "%User Profile%\Application Data\lssass.exe"
Step 4
Search and delete these components
- %User Temp%\NY.exe
- %User Temp%\JX.exe
- %User Temp%\QZ.exe
- %User Temp%\WX.exe
- %User Temp%\YZ.exe
- %User Temp%\YJ.exe
- %User Temp%\GG.exe
- %User Temp%\YW.exe
- %User Temp%\WO.exe
- %User Temp%\GW.exe
- %User Temp%\HO.exe
- %User Profile%\Application Data\lssass.exe
Step 5
Restart in normal mode and scan your computer with your Trend Micro product for files detected as WORM_UTOTI.MUL. 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 6
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%\58e0ef.mst
- %User Temp%\AdobeARM.log
- %User Temp%\AdobeSFX.log
- %User Temp%\ASPNETSetup_00000.log
- %User Temp%\ASPNETSetup_00001.log
- %User Temp%\ASPNETSetup_00002.log
- %User Temp%\dd_depcheck_NETFX_EXP_35.txt
- %User Temp%\dd_dotnetfx35error.txt
- %User Temp%\dd_dotnetfx35install.txt
- %User Temp%\dd_dotNetFx40_Full_x86_x64_decompression_log.txt
- %User Temp%\dd_MSXML6_MSI0686.txt
- %User Temp%\dd_netfx20MSI7F16.txt
- %User Temp%\dd_netfx20UI7F16.txt
- %User Temp%\dd_NET_Framework20_Setup06A7.txt
- %User Temp%\dd_NET_Framework30_Setup0775.txt
- %User Temp%\dd_NET_Framework35_MSI07B9.txt
- %User Temp%\dd_RGB9RAST_x86.msi0683.txt
- %User Temp%\dd_vcredistMSI3CAA.txt
- %User Temp%\dd_vcredistMSI7C21.txt
- %User Temp%\dd_vcredistUI3CAA.txt
- %User Temp%\dd_vcredistUI7C21.txt
- %User Temp%\dd_wcf_CA_smci_20111017_044900_062.txt
- %User Temp%\dd_wcf_retCA29BA.txt
- %User Temp%\dd_WIC.txt
- %User Temp%\dd_XPS.txt
- %User Temp%\Microsoft .NET Framework 4 Setup_20111016_234618578-MSI_netfx_Core_x86.msi.txt
- %User Temp%\Microsoft .NET Framework 4 Setup_20111016_234618578-MSI_netfx_Extended_x86.msi.txt
- %User Temp%\Microsoft .NET Framework 4 Setup_20111016_234618578.html
- %User Temp%\Microsoft Visual C++ 2010 x86 Redistributable Setup_20111020_000954642-MSI_vc_red.msi.txt
- %User Temp%\Microsoft Visual C++ 2010 x86 Redistributable Setup_20111020_000954642.html
- %User Temp%\NonFound
- %User Profile%\Application Data\lssass.exe
- %User Temp%\{malware file name}32_d.exe
- %User Temp%\JX32_H.exe
- %User Temp%\NY32_O.exe
- %User Temp%\QZ32_V.exe
- %User Temp%\uxeventlog.txt
- %User Temp%\vminst.log_20111016_212239_Failed.log
- %User Temp%\vminst.log_20130313_012028.log
- %User Temp%\vminst.log_20130313_012352_Failed.log
- %User Temp%\vmmsi.log_20111016_212246_Failed.log
- %User Temp%\vmmsi.log_20130313_012028.log
- %User Temp%\vmmsi.log_20130313_012352_Failed.log
- %User Temp%\WSFF8.tmp
- %User Temp%\WSFF9.tmp
- %User Temp%\GG32_S.exe
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