WORM_MOLDYOW.SMB
Suspicious.MH690 (Symantec); Trojan.Win32.Generic!BT (Sunbelt); Win32/Heur (AVG)
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
110,396 bytes
EXE
No
21 Oct 2013
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 creates the following folders:
- %Windows%\LastGood
- %Windows%\LastGood\INF
(Note: %Windows% is the Windows folder, which is usually C:\Windows.)
Other System Modifications
This worm deletes the following files:
- %Windows%\INF\SET15.tmp
- %Windows%\INF\WinSocks.sys
- %Windows%\INF\SET1C.tmp
- %Windows%\INF\WinSocksmp.inf
(Note: %Windows% is the Windows folder, which is usually C:\Windows.)
It adds the following registry keys:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
Explorer\Wdica
HKEY_CURRENT_USER\Software\Microsoft\
Driver Signing
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Network\NetCfgLockHolder
HKEY_LOCAL_MACHINE\System\CurrentControlSet\
Control\Network\{4d36e974-e325-11ce-bfc1-08002be10318}\
{992047C3-31B1-4CB9-BBDA-AD3C9D44CB92}
It adds the following registry entries:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
Explorer\Wdica
ErrorControl = "1"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
Explorer\Wdica
ImagePath = "inf\wdica.sys"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
Explorer\Wdica
Start = "2"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
Explorer\Wdica
Type = "1"
HKEY_CURRENT_USER\Software\Microsoft\
Driver Signing
Policy = "0"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\
{992047C3-31B1-4CB9-BBDA-AD3C9D44CB92}
Characteristics = "4418"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\
{992047C3-31B1-4CB9-BBDA-AD3C9D44CB92}
InfPath = "%Windows%\inf\oem13.inf"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\
{992047C3-31B1-4CB9-BBDA-AD3C9D44CB92}
InfSection = "WinSocks.ndi"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\
{992047C3-31B1-4CB9-BBDA-AD3C9D44CB92}
Description = "Microsoft WinSocks Driver Driver"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\
{992047C3-31B1-4CB9-BBDA-AD3C9D44CB92}
ComponentId = "ms_WinSocks"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\
{992047C3-31B1-4CB9-BBDA-AD3C9D44CB92}
InfPath = "oem13.inf"
It modifies the following registry entries:
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Network
Config = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\NdisWan\Linkage
Bind = "{random characters}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\NdisWan\Linkage
Route = "{random characters}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\NdisWan\Linkage
Export = "{random characters}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\
0008
NetCfgInstanceId = "{CA2DC9DA-D586-4464-91E8-EF8932205E21}"
(Note: The default value data of the said registry entry is {8347DFC0-2E88-4957-B577-F094C14F659F}.)
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\
0008\Linkage
RootDevice = "NdisWanIp"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\
0008\Linkage
UpperBind = "Tcpip"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\
0008\Linkage
Export = "\Device\NdisWanIp"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\
0001
NetCfgInstanceId = "{706C9A23-9058-4780-9179-0EE8467AACB4}"
(Note: The default value data of the said registry entry is {865B16A3-D78E-483F-8D7B-8DF6BB83FF7F}.)
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\
0001\Linkage
RootDevice = "{706C9A23-9058-4780-9179-0EE8467AACB4}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\
0001\Linkage
UpperBind = "Ndisuio,RasPppoe,Tcpip"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\
0001\Linkage
Export = "\Device\{706C9A23-9058-4780-9179-0EE8467AACB4}"
(Note: The default value data of the said registry entry is {random values}.)
Dropping Routine
This worm drops the following files:
- %System%\WinSocks.sys
- %Windows%\inf\WinSock2.PNF
- %Windows%\inf\Wdica.sys
- %Windows%\inf\Wdica.hiv
- %Windows%\inf\sigtab.dll
- %System%\WinSocks.inf
- %System%\WinSocksmp.inf
- %Windows%\INF\oem13.PNF
- %Windows%\inf\INFCACHE.0
- %Windows%\inf\ndistcp.pnf
- %Windows%\INF\oem13.inf
- %Windows%\INF\SET15.tmp
- %Windows%\INF\SET1C.tmp
- %Windows%\inf\WinSocks.inf
(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
9.300
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
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\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\Explorer
- Wdica
- In HKEY_CURRENT_USER\Software\Microsoft
- Driver Signing
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Network
- NetCfgLockHolder
- In HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Network\{4d36e974-e325-11ce-bfc1-08002be10318}
- {992047C3-31B1-4CB9-BBDA-AD3C9D44CB92}
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\policies\Explorer\Wdica
- ErrorControl = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\Explorer\Wdica
- ImagePath = "inf\wdica.sys"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\Explorer\Wdica
- Start = "2"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\Explorer\Wdica
- Type = "1"
- In HKEY_CURRENT_USER\Software\Microsoft\Driver Signing
- Policy = "0"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\{992047C3-31B1-4CB9-BBDA-AD3C9D44CB92}
- Characteristics = "4418"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\{992047C3-31B1-4CB9-BBDA-AD3C9D44CB92}
- InfPath = "%Windows%\inf\oem13.inf"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\{992047C3-31B1-4CB9-BBDA-AD3C9D44CB92}
- InfSection = "WinSocks.ndi"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\{992047C3-31B1-4CB9-BBDA-AD3C9D44CB92}
- Description = "Microsoft WinSocks Driver Driver"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\{992047C3-31B1-4CB9-BBDA-AD3C9D44CB92}
- ComponentId = "ms_WinSocks"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\{992047C3-31B1-4CB9-BBDA-AD3C9D44CB92}
- InfPath = "oem13.inf"
Step 4
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\SYSTEM\ControlSet001\Control\Network
- From: Config = "{random values}"
To: Config = ""{random values}""
- From: Config = "{random values}"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\NdisWan\Linkage
- From: Bind = "{random characters}"
To: Bind = ""{random values}""
- From: Bind = "{random characters}"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\NdisWan\Linkage
- From: Route = "{random characters}"
To: Route = ""{random values}""
- From: Route = "{random characters}"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\NdisWan\Linkage
- From: Export = "{random characters}"
To: Export = ""{random values}""
- From: Export = "{random characters}"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\0008
- From: NetCfgInstanceId = "{CA2DC9DA-D586-4464-91E8-EF8932205E21}"
To: NetCfgInstanceId = ""{8347DFC0-2E88-4957-B577-F094C14F659F}""
- From: NetCfgInstanceId = "{CA2DC9DA-D586-4464-91E8-EF8932205E21}"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\0008\Linkage
- From: RootDevice = "NdisWanIp"
To: RootDevice = ""{random values}""
- From: RootDevice = "NdisWanIp"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\0008\Linkage
- From: UpperBind = "Tcpip"
To: UpperBind = ""{random values}""
- From: UpperBind = "Tcpip"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\0008\Linkage
- From: Export = "\Device\NdisWanIp"
To: Export = ""{random values}""
- From: Export = "\Device\NdisWanIp"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\0001
- From: NetCfgInstanceId = "{706C9A23-9058-4780-9179-0EE8467AACB4}"
To: NetCfgInstanceId = ""{865B16A3-D78E-483F-8D7B-8DF6BB83FF7F}""
- From: NetCfgInstanceId = "{706C9A23-9058-4780-9179-0EE8467AACB4}"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\0001\Linkage
- From: RootDevice = "{706C9A23-9058-4780-9179-0EE8467AACB4}"
To: RootDevice = ""{random values}""
- From: RootDevice = "{706C9A23-9058-4780-9179-0EE8467AACB4}"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\0001\Linkage
- From: UpperBind = "Ndisuio,RasPppoe,Tcpip"
To: UpperBind = ""{random values}""
- From: UpperBind = "Ndisuio,RasPppoe,Tcpip"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\0001\Linkage
- From: Export = "\Device\{706C9A23-9058-4780-9179-0EE8467AACB4}"
To: Export = ""{random values}""
- From: Export = "\Device\{706C9A23-9058-4780-9179-0EE8467AACB4}"
Step 5
Search and delete these components
- %System%\WinSocks.sys
- %Windows%\inf\WinSock2.PNF
- %Windows%\inf\Wdica.sys
- %Windows%\inf\Wdica.hiv
- %Windows%\inf\sigtab.dll
- %System%\WinSocks.inf
- %System%\WinSocksmp.inf
- %Windows%\INF\oem13.PNF
- %Windows%\inf\INFCACHE.0
- %Windows%\inf\ndistcp.pnf
- %Windows%\INF\oem13.inf
- %Windows%\INF\SET15.tmp
- %Windows%\INF\SET1C.tmp
- %Windows%\inf\WinSocks.inf
Step 6
Search and delete these folders
- %Windows%\LastGood
- %Windows%\LastGood\INF
Step 7
Scan your computer with your Trend Micro product to delete files detected as WORM_MOLDYOW.SMB. 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.
- %Windows%\INF\SET15.tmp
- %Windows%\INF\WinSocks.sys
- %Windows%\INF\SET1C.tmp
- %Windows%\INF\WinSocksmp.inf
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