TROJ_DISKEN.A
TrojanDropper:Win32/Delfdru.gen!A (Microsoft); Generic Dropper.cv (McAfee); Trojan.Farfli (Symantec); Trojan-Dropper.Win32.Delf.anc (Kaspersky); Packer.NSAnti.Gen (v), TrojanDropper.Win32.Agent.ONO (v) (Sunbelt); MemScan:Trojan.Magania.ON (FSecure)
Windows 2000, Windows XP, Windows Server 2003
Threat Type: Trojan
Destructiveness: No
Encrypted:
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.
TECHNICAL DETAILS
1,845,652 bytes
EXE
Yes
17 Apr 2012
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.
Autostart Technique
This Trojan registers as a system service to ensure its automatic execution at every system startup by adding the following registry keys:
HKEY_LOCAL_MACHINE\system\cURRENTcONTROLsET\
sERVICES\WINSER_0x0\Parameters
Other System Modifications
This Trojan deletes the following files:
- %Windows%\fonts\msgothic.ttf
- %Windows%\fonts\msuigoth.ttf
- %Windows%\fonts\MSMINCHO.TTF
- %Windows%\fonts\Gulim.ttf
- %Windows%\fonts\Gulimche.ttf
- %Windows%\fonts\Dotum.ttf
- %Windows%\fonts\Batang.ttf
- %Windows%\fonts\Gungsuh.ttf
- %Windows%\fonts\Simsun.ttf
- %Windows%\fonts\nsimsun.ttf
- %Windows%\fonts\MingLiU.ttf
- %Windows%\fonts\pmingliu.ttf
- %System%\SET2.tmp
- %System%\kbd101b.dll
- %System%\SET4.tmp
- %System%\kbd101c.dll
- %System%\SET6.tmp
- %System%\kbd103.dll
- %System%\SET8.tmp
- %System%\kbd106.dll
- %System%\SETA.tmp
- %System%\kbdjpn.dll
- %System%\SETC.tmp
- %System%\kbdkor.dll
- %User Temp%\hests.exe
(Note: %Windows% is the Windows folder, which is usually C:\Windows.. %System% is the Windows system folder, which is usually C:\Windows\System32.. %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\Microsoft\
Internet Explorer\International\CpMRU
HKEY_LOCAL_MACHINE\??????????????????????
It adds the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\International\CpMRU
Enable = "1"
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\International\CpMRU
Size = "a"
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\International\CpMRU
InitHits = "64"
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\International\CpMRU
Factor = "14"
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\International
W2KLpk = "1"
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\International
W2KLpk = "0"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\WINSER_0x0
Description = "{random characters}"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\WINSER_0x0\Parameters
ServiceDll = "%User Profile%\DRM\wab32er.dll"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\WINSER_0x0
iNSTALLmODULE = "%User Temp%\hests.exe"
It modifies the following registry entries:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\SvcHost
netsvcs = "{random characters}"
(Note: The default value data of the said registry entry is {random values}.)
Dropping Routine
This Trojan drops the following files:
- %User Temp%\ºêºêQQ´óµÁ3.0.exe
- %User Temp%\hests.exe
- %System%\SET1.tmp
- %System%\SET3.tmp
- %System%\SET5.tmp
- %System%\SET7.tmp
- %System%\SET9.tmp
- %System%\SETB.tmp
- %User Profile%\DRM\wab32er.dll
- %System%\SET2.tmp
- %System%\SET4.tmp
- %System%\SET6.tmp
- %System%\SET8.tmp
- %System%\SETA.tmp
- %System%\SETC.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.. %System% is the Windows system folder, which is usually C:\Windows\System32.. %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 Trojan connects to the following possibly malicious URL:
- http://hi.{BLOCKED}u.com/{random path}
This report is generated via an automated analysis system.
SOLUTION
9.200
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 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\system\cURRENTcONTROLsET\sERVICES\WINSER_0x0
- Parameters
- In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\International
- CpMRU
- In HKEY_LOCAL_MACHINE
- ??????????????????????
Step 4
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\International\CpMRU
- Enable = "1"
- In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\International\CpMRU
- Size = "a"
- In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\International\CpMRU
- InitHits = "64"
- In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\International\CpMRU
- Factor = "14"
- In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\International
- W2KLpk = "1"
- In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\International
- W2KLpk = "0"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\WINSER_0x0
- Description = "{random characters}"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\WINSER_0x0\Parameters
- ServiceDll = "%User Profile%\DRM\wab32er.dll"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\WINSER_0x0
- iNSTALLmODULE = "%User Temp%\hests.exe"
Step 5
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\SOFTWARE\Microsoft\Windows NT\CurrentVersion\SvcHost
- From: netsvcs = "{random characters}"
To: netsvcs = ""{random values}""
- From: netsvcs = "{random characters}"
Step 6
Search and delete these components
- %User Temp%\ºêºêQQ´óµÁ3.0.exe
- %User Temp%\hests.exe
- %System%\SET1.tmp
- %System%\SET3.tmp
- %System%\SET5.tmp
- %System%\SET7.tmp
- %System%\SET9.tmp
- %System%\SETB.tmp
- %User Profile%\DRM\wab32er.dll
- %System%\SET2.tmp
- %System%\SET4.tmp
- %System%\SET6.tmp
- %System%\SET8.tmp
- %System%\SETA.tmp
- %System%\SETC.tmp
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_DISKEN.A. 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%\fonts\msgothic.ttf
- %Windows%\fonts\msuigoth.ttf
- %Windows%\fonts\MSMINCHO.TTF
- %Windows%\fonts\Gulim.ttf
- %Windows%\fonts\Gulimche.ttf
- %Windows%\fonts\Dotum.ttf
- %Windows%\fonts\Batang.ttf
- %Windows%\fonts\Gungsuh.ttf
- %Windows%\fonts\Simsun.ttf
- %Windows%\fonts\nsimsun.ttf
- %Windows%\fonts\MingLiU.ttf
- %Windows%\fonts\pmingliu.ttf
- %System%\SET2.tmp
- %System%\kbd101b.dll
- %System%\SET4.tmp
- %System%\kbd101c.dll
- %System%\SET6.tmp
- %System%\kbd103.dll
- %System%\SET8.tmp
- %System%\kbd106.dll
- %System%\SETA.tmp
- %System%\kbdjpn.dll
- %System%\SETC.tmp
- %System%\kbdkor.dll
- %User Temp%\hests.exe
Did this description help? Tell us how we did.