TROJ_DANMEC.BI
Trojan:Win32/Danmec.L (Microsoft); Generic.dx!bcjm (McAfee); Trojan.Gen (Symantec); Trojan.Win32.Yakes.lrd (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Trojan.Generic.KD.497526 (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
139,264 bytes
EXE
Yes
16 Nov 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.
Installation
This Trojan creates the following folders:
- %User Profile%\Microsoft\Protect
(Note: %User Profile% is the current user's profile folder, which is usually C:\Windows\Profiles\{user name} on Windows 98 and ME, C:\WINNT\Profiles\{user name} on Windows NT, and C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003.)
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
sfekhyv = "rundll32 %User Profile%\Protect\gcyqen.ya, rbcf"
Other System Modifications
This Trojan adds the following registry keys:
HKEY_LOCAL_MACHINE\Software\Microsoft\
Sft
It modifies the following registry entries:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
DirectDraw\MostRecentApplication
Name = "iexplore.exe"
(Note: The default value data of the said registry entry is iexplore.exe.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
DirectDraw\MostRecentApplication
ID = "4117b81"
(Note: The default value data of the said registry entry is 41107b81.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
SystemCertificates\CA\Certificates\
8B24CD8D8B58C6DA72ACE097C7B1E3CEA4DC3DC6
Blob = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
Dropping Routine
This Trojan drops the following files:
- %User Profile%\Protect\gcyqen.ya
- %User Profile%\Protect\s32.txt
(Note: %User Profile% is the current user's profile folder, which is usually C:\Windows\Profiles\{user name} on Windows 98 and ME, C:\WINNT\Profiles\{user name} on Windows NT, and C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003.)
This report is generated via an automated analysis system.
SOLUTION
9.300
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
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\Software\Microsoft
- Sft
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
- sfekhyv = "rundll32 %User Profile%\Protect\gcyqen.ya, rbcf"
Step 5
Restore this modified 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\DirectDraw\MostRecentApplication
- From: Name = "iexplore.exe"
To: Name = ""iexplore.exe""
- From: Name = "iexplore.exe"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\DirectDraw\MostRecentApplication
- From: ID = "4117b81"
To: ID = ""41107b81""
- From: ID = "4117b81"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\SystemCertificates\CA\Certificates\8B24CD8D8B58C6DA72ACE097C7B1E3CEA4DC3DC6
- From: Blob = "{random values}"
To: Blob = ""{random values}""
- From: Blob = "{random values}"
Step 6
Search and delete these files
- %User Profile%\Protect\gcyqen.ya
- %User Profile%\Protect\s32.txt
Step 7
Search and delete this folder
- %User Profile%\Microsoft\Protect
Step 8
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_DANMEC.BI. 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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