TROJ_DLOADR.BRK
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.
It deletes itself after execution.
TECHNICAL DETAILS
57,856 bytes
EXE
Yes
07 Sep 2013
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%\YouPin.exe
(Note: %System% is the Windows system folder, which is usually C:\Windows\System32.)
Autostart Technique
This Trojan adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
YouPin = "%System%\YouPin.exe"
Other System Modifications
This Trojan modifies the following file(s):
- %Windows%\inf\intl.PNF
(Note: %Windows% is the Windows folder, which is usually C:\Windows.)
It 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%\SETB.tmp
- %System%\kbd101b.dll
- %System%\SET11.tmp
- %System%\kbd101c.dll
- %System%\SET17.tmp
- %System%\kbd103.dll
- %System%\SET1D.tmp
- %System%\kbd106.dll
- %System%\SET23.tmp
- %System%\kbdjpn.dll
- %System%\SET29.tmp
- %System%\kbdkor.dll
(Note: %Windows% is the Windows folder, which is usually C:\Windows.. %System% is the Windows system folder, which is usually C:\Windows\System32.)
It adds the following registry keys:
HKEY_CURRENT_USER\Software\Microsoft\
Windows Script\Settings
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\International\CpMRU
It adds the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
Windows Script\Settings
JITDebug = "0"
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"
Dropping Routine
This Trojan drops the following files:
- %System%\SET8.tmp
- %System%\SETE.tmp
- %System%\SET14.tmp
- %System%\SET1A.tmp
- %System%\SET20.tmp
- %System%\SET26.tmp
- %System%\SETB.tmp
- %System%\SET11.tmp
- %System%\SET17.tmp
- %System%\SET1D.tmp
- %System%\SET23.tmp
- %System%\SET29.tmp
(Note: %System% is the Windows system folder, which is usually C:\Windows\System32.)
Other Details
This Trojan deletes itself after execution.
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
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_CURRENT_USER\Software\Microsoft\Windows Script
- Settings
- In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\International
- CpMRU
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_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
- YouPin = "%System%\YouPin.exe"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows Script\Settings
- JITDebug = "0"
- 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"
Step 5
Search and delete these components
- %System%\SET8.tmp
- %System%\SETE.tmp
- %System%\SET14.tmp
- %System%\SET1A.tmp
- %System%\SET20.tmp
- %System%\SET26.tmp
- %System%\SETB.tmp
- %System%\SET11.tmp
- %System%\SET17.tmp
- %System%\SET1D.tmp
- %System%\SET23.tmp
- %System%\SET29.tmp
Step 6
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_DLOADR.BRK. 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 7
Restore deleted/modified files and/or registry entries from backup
*Note: Only Microsoft-related files/keys/values will be restored. If this malware/grayware also deleted registry keys/values related to programs that are not from Microsoft, please reinstall those programs on your computer.
- %Windows%\inf\intl.PNF
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%\SETB.tmp
- %System%\kbd101b.dll
- %System%\SET11.tmp
- %System%\kbd101c.dll
- %System%\SET17.tmp
- %System%\kbd103.dll
- %System%\SET1D.tmp
- %System%\kbd106.dll
- %System%\SET23.tmp
- %System%\kbdjpn.dll
- %System%\SET29.tmp
- %System%\kbdkor.dll
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